tag:blogger.com,1999:blog-44300658420593586222024-03-29T18:05:26.476+03:00My TCEC ExperienceAssaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.comBlogger620125tag:blogger.com,1999:blog-4430065842059358622.post-77945776376830133012024-03-21T09:46:00.013+02:002024-03-27T10:18:05.541+02:00Season 26 entrance league<p>The engines that will play in the season 26 entrance league are:</p><p>relegated from season 25 league 2: Velvet Tucano Wasp<br />played in season 25 entrance league: Booot Weiss Equisetum Winter Expositor Stash<br />new to TCEC (played in Swiss tournament): Obsidian Willow Stormphrax akimbo Altair<br />returning to TCEC: Berserk (season 24 premier division) Texel (season 17 league 2)</p><p><b>Final standings</b></p><p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgzEby9BDJWYHH0NdBmfqctx9dUQ3KxZqdpmqTse8fDY2OAAAdNP9Q9Jcj1Gi-aSkcR4QLsIa8YIv0vgq-Vh5Xfgi7WV4h7JnTX74r7gROm2TFpRPa73zyLA6XtJ5jRlvwOp28j5nvXGq_QETeoklR8W9VR1opHFe564l30JrvadZM2mBx0Ih3ixXH6p8E/s645/tab1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="645" data-original-width="604" height="400" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgzEby9BDJWYHH0NdBmfqctx9dUQ3KxZqdpmqTse8fDY2OAAAdNP9Q9Jcj1Gi-aSkcR4QLsIa8YIv0vgq-Vh5Xfgi7WV4h7JnTX74r7gROm2TFpRPa73zyLA6XtJ5jRlvwOp28j5nvXGq_QETeoklR8W9VR1opHFe564l30JrvadZM2mBx0Ih3ixXH6p8E/w375-h400/tab1.jpg" width="375" /></a></div><br /><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgnh55k_xPrXAO3yG9T9XnDGhZx36_6oNHc-xtYrk3bIsquFrvWxMUUbJrHQ9_JBBURsGpke0CNwrjLlqMjRRgXNxZp2s664DTLqQ7kU5sNKEFucnKUHjrZAfmb_xhMNR1YKFiXs9ow3pfMgUE-PwqxXo_VNsP-iFRMdybshrW52WpyE0G7C94N7I9sHWk/s637/tab2.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="637" data-original-width="561" height="400" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgnh55k_xPrXAO3yG9T9XnDGhZx36_6oNHc-xtYrk3bIsquFrvWxMUUbJrHQ9_JBBURsGpke0CNwrjLlqMjRRgXNxZp2s664DTLqQ7kU5sNKEFucnKUHjrZAfmb_xhMNR1YKFiXs9ow3pfMgUE-PwqxXo_VNsP-iFRMdybshrW52WpyE0G7C94N7I9sHWk/w353-h400/tab2.jpg" width="353" /></a></div><br /><b><br /></b><p></p><p>Berserk, Obsidian, Velvet and Stormphrax advance to league 2. Berserk was the clear leader from the start, this was expected considering that it was in the premier division in season 24 and started in the entrance league because it didn't play in season 25. It won 13/15 game pairs with no loss. Obsidian and Velvet kept a small advantage over the other engines, Obsidian lost one game pair to Berserk while Velvet did not lose any game pair. There was a race for the fourth qualifying spot, with Storphrax and Altair leading and Equisetum and Booot not far behind. Altair had a small lead with two rounds left, but then Stormphrax won a game as black (against the bias, the only such win in the league) and equalized. Stormphrax advanced on a tiebreak.</p><p>The 4 qualifiers will play in league 2 together with:<br />played in season 25 league 1: Viridithas, ScorpioNN, Ginkgo (replaces Fritz), DeepSjeng<br />played in season 25 league 2: Arasan, BlackMarlin, Uralochka, Marvin</p><p><b>Interesting games</b></p><p><a href="https://tcec-chess.com/#div=el&game=14&season=26">game 14</a>, <span style="background-color: #04ff00;">Berserk</span> - Weiss: Berserk captured a pawn and attacked on the king side. Weiss reduced to a RB vs RN position, Berserk slowly captured black pawns until there were none left, then exchanged the minor pieces. Berserk queened a passer and won.</p><p><a href="https://tcec-chess.com/#div=el&game=18&season=26">game 18</a>, <span style="background-color: #04ff00;">Stormphrax</span> - Wasp: The position seemed drawn after many early exchanges, however Stormphrax played better with only RBN vs RBN left. It captured a pawn and created a passer on the 7th rank, then gave it back and reduced to a B vs N ending. Stormphrax created another passer and used it to win.</p><p><a href="https://tcec-chess.com/#div=el&game=19&season=26">game 19</a>, <span style="background-color: #04ff00;">Weiss</span> - Equisetum: Weiss had a passer on the queen side and a pawn majority on the king side, Equisetum had a passer in the center. Weiss created a second passer and exchanged queens, the game eventually reached a rook ending. Equisetum captured one passer but lost more pawns, the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=el&game=24&season=26">game 24</a>, <span style="background-color: #04ff00;">Velvet</span> - Booot: Velvet skewered rook and queen after Booot chose a bad square for its rook. Velvet captured a rook for a bishop, then later gave back the material for a passer in the center. Velvet gave its queen for a rook to connect a second passer and then queened one. The rook advantage was enough for a win.</p><p><a href="https://tcec-chess.com/#div=el&game=29&season=26">game 29</a>, <span style="background-color: #04ff00;">Berserk</span> - Tucano: Berserk opened the queen side and created a passer, Tucano gave two pawns and pushed a passer to the 2nd rank. Berserk blocked with a rook, Tucano gave a rook for a bishop to capture the white passer. Berserk opened the king side, reduced to a QRB vs QBN position and captured the black passer. The black king was exposed and the game ended in mate.</p><p><a href="https://tcec-chess.com/#div=el&game=33&season=26">game 33</a>, <span style="background-color: #04ff00;">Stormphrax</span> - akimbo: The engines castled in opposite directions, both created passers on the same side as their king. The game reached a RBN vs RNN position and Stormphrax went a pawn up. akimbo had a passer on the 3rd rank that was blocked, Stormphrax traded knights and captured a second pawn. The game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=el&game=44&season=26">game 44</a>, <span style="background-color: #04ff00;">Berserk</span> - Obsidian: Berserk was a pawn up in a QRN vs QRB position, it managed to get its major pieces to the back rank and threatened the black king. Berserk reduced to a queen ending, then slowly pushed its king forward. Obsidian couldn't avoid a queening and the game ended in mate.</p><p><a href="https://tcec-chess.com/#div=el&game=45&season=26">game 45</a>, <span style="background-color: #04ff00;">Equisetum</span> - Winter: The engines castled in opposite directions and Equisetum attacked the king side. It gave a pawn and moved its major pieces to threaten the black king. Winter gave the pawn back, creating a white passer on the 7th rank. Equisetum went two pawns up, gave up the passer and reduced to a winning rook ending.</p><p><a href="https://tcec-chess.com/#div=el&game=60&season=26">game 60</a>, <span style="background-color: #04ff00;">Equisetum</span> - Velvet: Queens were off early and both kings moved without castling, the engines reduced to a RB vs RN position. Equisetum moved its rook to the 7th rank, the black pieces defended pawns passively. The white king moved forward, after exchanging minor pieces Equisetum captured two pawns. The game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=el&game=67&season=26">game 67</a>, <span style="background-color: #04ff00;">Winter</span> - Stormphrax: There were only a few exchanges after the start and the position was closed for a long time. After exchanging queens Stormphrax gave a knight for 4 pawns and the position opened. The game reached a RBB vs RB position, Winter slowly captured pawns and by move 114 each engine had two remaining pawns. Winter queened a passer and mated.</p><p><a href="https://tcec-chess.com/#div=el&game=68&season=26">game 68</a>, <span style="background-color: #04ff00;">Obsidian</span> - Willow: Willow kept its king uncastled and struggled to develop its king side rook. The rook was exchanged a few moves after it was freed, and the game reached a RBN vs RBN position. Obsidian went a pawn up, Willow gave a bishop for a pawn to avoid connected passers. Stormphrax reduced to a tablebase win with one last pawn left.</p><p><a href="https://tcec-chess.com/#div=el&game=83&season=26">game 83</a>, <span style="background-color: #04ff00;">Obsidian</span> - Weiss: Obsidian had a pawn majority on the queen side and it pushed its pawns forward. The black pieces were mostly passive, the game reached a RRN vs RRB position with white a pawn up. Weiss lost more material and the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=el&game=84&season=26">game 84</a>, <span style="background-color: #04ff00;">Velvet</span> - Stormphrax: Stormphrax gave a pawn and the engines opened the king side. All rooks and most pawns were exchanged, Stormphrax pushed a passer forward and Velvet gave a bishop to stop it. The white king was exposed to check but eventually found a safe square, the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=el&game=104&season=26">game 104</a>, <span style="background-color: #04ff00;">Berserk</span> - Equisetum: Berserk went up a pawn, the engines slowly exchanged pieces and the game reached a QB vs QN position. Berserk created a passer, Equisetum captured it but Berserk created another and reduced to a queen ending. The engines traded pawns and the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=el&game=105&season=26">game 105</a>, <span style="background-color: #04ff00;">akimbo</span> - Equisetum: akimbo went up a pawn, Equisetum traded both its bishops for white knights. The game reached a RBB vs RNN position, akimbo had a passer in the center blocked by a knight. akimbo increased the pressure and eventually captured a knight for a pawn, then captured the remaining black pawns and forced mate.</p><p><a href="https://tcec-chess.com/#div=el&game=110&season=26">game 110</a>, <span style="background-color: #04ff00;">Altair</span> - Booot: There were only a few exchanges after the start, the engines mostly shuffled. After move 47 Booot exposed the white king while Altair pushed a passer to the 7th rank. Booot lost a knight for the passer, Altair created more passers and Booot lost more material until it was mated.</p><p><a href="https://tcec-chess.com/#div=el&game=113&season=26">game 113</a>, <span style="background-color: #04ff00;">Obsidian</span> - akimbo: Evals started to increase after move 25, a series of exchanges opened the center 15 moves later. The game reached a rook ending, Obsidian captured the isolated black pawns and pushed connected passers. The game ended in a tablebase win.</p><p><i>Standings after RR1: Berserk +7, Obsidian +5, Velvet +3, Stormphrax Altair +2, Equisetum +1, Willow Tucano akimbo 0, Booot Wasp Weiss -1, Texel -3, Winter Stash -4, Expositor -6. Berserk leads after winning all games as white and drawing all games as black. Obsidian in 2nd place has only one loss to Berserk. Of the new engines Stormphrax and Altair also have a good chance of advancing, Altair has no loss so far.</i></p><p><a href="https://tcec-chess.com/#div=el&game=122&season=26">game 122</a>, <span style="background-color: #04ff00;">Equisetum</span> - Willow: The engines shuffled for a long time, on move 113 they started to exchange pieces and pawns and the game reached a RB vs RB position. Equisetum was a pawn up with a passer, after another long shuffle Equisetum found a way to improve. It used a passer to capture a piece, the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=el&game=138&season=26">game 138</a>, <span style="background-color: #04ff00;">Wasp</span> - Stormphrax: Both engines had a passer in the center, but the black passer was isolated. Wasp placed a strong bishop on f6, after some shuffling Stormprax decided to exchange the bishop for a rook. Both passers were captured, the game reached a RR vs RN position. Wasp captured all the remaining black pawns, the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=el&game=140&season=26">game 140</a>, <span style="background-color: #04ff00;">Berserk</span> - Altair: Berserk created a passer in the center, then gave a rook and two pawns for a bishop to push the passer to the 6th rank. The game reached a RBB vs RRN position, Altair also pushed a passer forward but it had a pinned rook. Eventually both passers were captured and the engines reduced to a RB vs R ending with black two pawns up. The game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=el&game=145&season=26">game 145</a>, <span style="background-color: #04ff00;">Booot</span> - akimbo: The engines castled in opposite directions and Booot tried to attack on the king side. In a series of exchanges Booot traded BN for R and opened files, creating a passer. akimbo played inaccurately, after exchanging queens Booot pushed the passer forward, akimbo lost a knight for it. The game reached a RN vs BN position and ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=el&game=152&season=26">game 152</a>, <span style="background-color: #04ff00;">Stormphrax</span> - Willow: In a series of exchanges the engines reduced to a QRR vs QRR position with white a pawn up. All rooks were then exchanged and Stormphrax created a pawn majority on the queen side. Stormphrax captured another pawn and exchanged queens, the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=el&game=167&season=26">game 167</a>, <span style="background-color: #04ff00;">Altair</span> - Willow: The game reached a RN vs RN position with white a pawn up and all pawns on the king side. The engines shuffled and exchanged rooks, on move move 67 Willow played the wrong knight move. The white king managed to move behind the black pawns, Altair captured two pawns and won.</p><p><a href="https://tcec-chess.com/#div=el&game=177&season=26">game 177</a>, <span style="background-color: #04ff00;">Texel</span> - akimbo: Texel slowly moved its pieces to the king side in a closed position, then opened the king side in a series of exchanges that started on move 41. Texel gave 3 pawns and attacked the black king, akimbo lost material and the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=el&game=180&season=26">game 180</a>, <span style="background-color: #04ff00;">Velvet</span> - Equisetum: Queens were off early and both kings moved without castling. Equisetum had a passer on the king side, it gave a rook for a knight and the engines reduced to a RR vs RB position. The black passer on the 3rd rank wasn't strong enough, Velvet managed to capture all the black pawns, queen a passer and mate.</p><p><a href="https://tcec-chess.com/#div=el&game=184&season=26">game 184</a>, <span style="background-color: #04ff00;">Altair</span> - Weiss: Weiss kept its king uncastled, blocking the king side rook. Altair opened the queen side and doubled queen and rook on the open c file. Weiss exchanged queens and the game reached a RRB vs RRB position. Altair created a passer, the black king side rook finally came out to block. Eventually Weiss lost both rooks for the passer, and Altair mated.</p><p><a href="https://tcec-chess.com/#div=el&game=197&season=26">game 197</a>, <span style="background-color: #04ff00;">Velvet</span> - Willow: Willow captured a pawn but Velvet trapped a black rook and captured it for a bishop. The engines reduced to a R vs B ending and the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=el&game=200&season=26">game 200</a>, <span style="background-color: #04ff00;">Tucano</span> - Altair: There were almost no exchanges after the start, the engines mainly shuffled for a long time. Altair pushed pawns on the queen side and after a pawn exchange on move 43 the queen side opened. The first pieces were exchanged on move 50. Tucano blocked a black passer on the queen side and created a passer in the center. Altair gave a knight for two pawns and tried to attack the white king, Tucano exchanged queens and pushed the passer to the 7th rank. The black king was trapped, Tucano finished the game with a rook sacrifice and a mate with minor pieces.</p><p><i>Standings with 5 rounds to go: Berserk +10, Obsidian +7, Velvet +6, Altair Stormphrax +3, Equisetum +2, Booot +1, akimbo Weiss Tucano -1, Willow Texel -2, Wasp -4, Stash -6, Expositor -7, Winter -8. The top three places are practically determined, the fourth engine to advance is still open. Both Altair and Stormphrax lost a game to a weaker engine (Wasp and Tucano), both have a good chance of advancing. Equisetum and Booot have a smaller chance, Booot has two critical games left as white against Altair and Stormphrax.</i></p><p><i>Top standings with 2 rounds to go: Berserk +12, Obsidian +7, Velvet +6, Altair +4, Stormphrax +3, Equisetum +2, Booot +1. The only changes after 3 more rounds are that Berserk extended its lead and Altair won a game and is now alone in fourth place. Equisetum failed to win as white against Texel, Booot drew as white against Stormphrax, both are unlikely to advance. Stormphrax failed to beat Expositor as white and its chance of catching Altair up are small. </i></p><p><a href="https://tcec-chess.com/#div=el&game=225&season=26">game 225</a>, <span style="background-color: #04ff00;">Equisetum</span> - akimbo: Equisetum captured a pawn early, the engines reduced to a RN vs RB position with white a pawn up. Equisetum had a passer, akimbo played inaccurately and after exchanging minor pieces Equisetum created a second passer. Equisetum then reduced to a tablebase win.</p><p><a href="https://tcec-chess.com/#div=el&game=228&season=26">game 228</a>, Texel - <span style="background-color: #04ff00;">Stormphrax</span>: Texel gave a pawn early, Stormphrax equalized easily and the engines mostly shuffled in a closed position. On move 113 Stormphrax opened the king side, it created two passers and pushed one to the 2nd rank. Stormphrax gave a rook for a bishop and captured more pawns. After exchanging queens Texel lost material to avoid a queening, and eventually was mated.</p><p><i>Top standings before the last round: </i><i>Berserk +13, Obsidian +8, Velvet +7, Altair Stormphrax +4, Equisetum +3, Booot +1. Stormphrax won a game as black, the only black win of the league. Booot drew as white against Altair and is out of the race. Stormphrax has a tiebreak advantage over Altair and now has a better chance of advancing. Equisetum is still in the race, but its last game is in black and its chances are very small.</i></p><p><i>In the last round Altair beat Expositor, but then Stormphrax beat Stash and Stormphrax advances on tiebreak.</i></p><p><i><br /></i></p>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com1tag:blogger.com,1999:blog-4430065842059358622.post-68880682661408872382023-11-11T15:58:00.001+02:002023-11-11T15:58:29.004+02:00Season 25 superfinal statistics<p>A summary <a href="https://drive.google.com/open?id=1dpikbAHWxz1wLcsOzG0kxKCk0Hn67IYJPL8B1wzj_rk" target="_blank">statistics table</a> of previous stages and seasons. <b></b><br /></p><p><b>Draw rate, wins</b></p><p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgeEKNkJhS7mIe9FN2XJZPM_nHRJ3g7-4k-xefyUvQNVMf2AQzokfUErx6pPxiu0M4JxOm8rTk_VOTJsnNSsF0GOU81qxNij9rAHK2UT_7B6_hLElfQEB5wxglK3gPyfpqIhnZ3kggJNusSrQ8PHswAkqQE5_FqrQMBT0XjwBuDvsLPYuDhvuZUExcFgqQ/s480/S25.sf.g1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgeEKNkJhS7mIe9FN2XJZPM_nHRJ3g7-4k-xefyUvQNVMf2AQzokfUErx6pPxiu0M4JxOm8rTk_VOTJsnNSsF0GOU81qxNij9rAHK2UT_7B6_hLElfQEB5wxglK3gPyfpqIhnZ3kggJNusSrQ8PHswAkqQE5_FqrQMBT0XjwBuDvsLPYuDhvuZUExcFgqQ/s320/S25.sf.g1.jpg" width="320" /></a></div>Final draw rate was 50%.<br /><p></p><div><p><b>Game termination</b></p><p>The three most common game termination causes were:</p>45% - TCEC draw rule<br />27% - Mate</div><div>24% - SyzygyTB<br /></div><div><br /></div><div>There were no crashes in the stage.<br /></div><p><b>Moves per game</b></p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg3xYDcqTO5jJZ8YtqIHMENjW6KrWGXl7DicPXNzbr7wm42GwA-cWs9kC2jk2wBnfFTX5QH2BVDmN7ezQsMt84485Qi5FtIXdxQtDsIipAjbIq4aQhmd7wJbvXz5bwtOR9qv35q8Mbj8eF4G0-EG7CgmwsBcG9-Vq3aAV7QD08EZjSWhyphenhyphen07U5_GHgfKKeA/s480/S25.sf.g2.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg3xYDcqTO5jJZ8YtqIHMENjW6KrWGXl7DicPXNzbr7wm42GwA-cWs9kC2jk2wBnfFTX5QH2BVDmN7ezQsMt84485Qi5FtIXdxQtDsIipAjbIq4aQhmd7wJbvXz5bwtOR9qv35q8Mbj8eF4G0-EG7CgmwsBcG9-Vq3aAV7QD08EZjSWhyphenhyphen07U5_GHgfKKeA/s320/S25.sf.g2.jpg" width="320" /></a></p><p>Median= 77<br />Average= 83.2<br /><br />There were 17 games longer than 100 moves, the longest was 379 moves (Stockfish - Leela, game 84, draw), a new TCEC record.<br /><br /><b>Time per game (hours) </b></p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjgfngB_T8ABu8LBa1VER3qHsVK5E9mlZIL-2h_jcbHAbWFz8EkkrEefsTiHRyhV0fRTDVaNYY3tyVkjGejTNW_LvmJ61-748mYBWo2YesafBO0AwrZ7OxxlorsZNkYComRMe9Xb-CVuG-tK4oziMZJ4aMyLq6UoCrYDHLwZg-KAwUJucYn7Gi90t3_yrU/s480/S25.sf.g3.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjgfngB_T8ABu8LBa1VER3qHsVK5E9mlZIL-2h_jcbHAbWFz8EkkrEefsTiHRyhV0fRTDVaNYY3tyVkjGejTNW_LvmJ61-748mYBWo2YesafBO0AwrZ7OxxlorsZNkYComRMe9Xb-CVuG-tK4oziMZJ4aMyLq6UoCrYDHLwZg-KAwUJucYn7Gi90t3_yrU/s320/S25.sf.g3.jpg" width="320" /></a></p><p>Median= 4:21<br />Average= 4:12<br /><br /><b>Openings</b><br /><br />There were variable length book openings in this stage chosen by Jeroen Noomen. The first letter of the ECO codes was distributed as follows:</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjmR5LWNe1MPbVm1C_XUjAJPmWh9HdmNU3zbnCoW7s_Cms0EJwf_OBUAMDdODh0JSI14Q2roaea7qUWgAWwKazSZkgIU_SwMq19KJZu7SSzdHi2LkuR3GA-hB7hUMkb2W653qFai_LEVBFNJdkp9GSaV1Gtyki9FXo_49tb-RfJU_r31_-JiaOjxfdqWy4/s480/S25.sf.g4.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjmR5LWNe1MPbVm1C_XUjAJPmWh9HdmNU3zbnCoW7s_Cms0EJwf_OBUAMDdODh0JSI14Q2roaea7qUWgAWwKazSZkgIU_SwMq19KJZu7SSzdHi2LkuR3GA-hB7hUMkb2W653qFai_LEVBFNJdkp9GSaV1Gtyki9FXo_49tb-RfJU_r31_-JiaOjxfdqWy4/s320/S25.sf.g4.jpg" width="320" /></a></p><p>The engines had almost no freedom to choose the opening variant, all the game pairs repeated the same ECO and the same opening variant twice.<br /><br /><b>Reverse pairs, wins </b></p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhRvBOFrnJ1UWXecmhDRsiRe1twd1ePtZW_0YECYBaH56zGZncbnzK9az-aNBaDH-FITer159iE5Q7cxY4KZaZuBkIncVxGFChGzssCuJ64RLbvgQxwwtrOeczz6FqB0n9f4ur8lV7sKVt8VEl1rGEhAzTzBHv1IxFgH9HkcOky5y2WVZ-tegoc-SvHxTk/s480/S25.sf.g5.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhRvBOFrnJ1UWXecmhDRsiRe1twd1ePtZW_0YECYBaH56zGZncbnzK9az-aNBaDH-FITer159iE5Q7cxY4KZaZuBkIncVxGFChGzssCuJ64RLbvgQxwwtrOeczz6FqB0n9f4ur8lV7sKVt8VEl1rGEhAzTzBHv1IxFgH9HkcOky5y2WVZ-tegoc-SvHxTk/s320/S25.sf.g5.jpg" width="320" /></a></p><p><b>Reverse pairs, same moves </b></p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhTMwqXg2nKpRyaYhusoU-VLECIvp27gPQBtP6EgXTqGTrM8zZ2tGub3Q9yLsw6Hhz134R3bsS_FjuDRED2fp3_NnNI-1uSP0IxN03wC-lAkahQ3DAjxiB_fJxckYHviSXiFKCX1LEVq0MxZ0MUeIkBkoIZU0pQvOEKrEhskxPjQnKQ1l-vMuWye0sGkHE/s480/S25.sf.g6.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhTMwqXg2nKpRyaYhusoU-VLECIvp27gPQBtP6EgXTqGTrM8zZ2tGub3Q9yLsw6Hhz134R3bsS_FjuDRED2fp3_NnNI-1uSP0IxN03wC-lAkahQ3DAjxiB_fJxckYHviSXiFKCX1LEVq0MxZ0MUeIkBkoIZU0pQvOEKrEhskxPjQnKQ1l-vMuWye0sGkHE/s320/S25.sf.g6.jpg" width="320" /></a></p><p>Pairs of reverse games diverged slower than usual, 8% diverged immediately out of book, 46% of the pairs diverged at most after 1 move. The longest repeated sequence of moves was 53 plys (Leela - Stockfish games 49 and 50, Modern defense, two draws).</p><p><br /></p>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com1tag:blogger.com,1999:blog-4430065842059358622.post-3659373826780923992023-11-01T22:49:00.004+02:002023-11-09T01:19:00.213+02:00Season 25 superfinal games 91-100, season summary<p>Stockfish is the winner of the season 25 superfinal. The final score is 27-23 with 50 draws. Leela won another game pair and reduced Stockfish's lead to 4, the same gap as in the previous superfinal. The other 4 game pairs were drawn, 3 of them with two white wins. In the last 18 game pairs Leela beat Stockfish 4-0 in game pair wins, while after the first 32 game pairs Stockfish led 9-1. </p><p>The superfinal started with 6 decisive games in 3 drawn game pairs. Stockfish won the first decisive game pair, and it slowly increased its lead. Of the first 14 game pairs Stockfish won 3, then Leela won its first game pair and Stockfish led by only 2 wins after 30 games. Stockfish then won several game pairs and increased its lead to 6 wins at the half way point. In some of the games Stockfish demonstrated superior endgame skills, for example in complex queen endgames. Stockfish extended its lead to a maximum of 8 wins after 32 game pairs, then Leela won its second pair of the match and reduced the lead to 7. From this point Stockfish did not win another game pair, it seemed that somehow Leela became stronger. Stockfish managed to get out of a game pair loss after a very late Leela inaccuracy in game 70. Leela slowly won more pairs, and the match ended with Stockfish ahead by 4 wins. Who knows what could have happened if more games were played.</p><p>Season 25 started with a <a href="https://mytcecexperience.blogspot.com/2023/07/season-25-qualificationswiss.html">Swiss event</a>, however unlike in the previous season this event was not considered a replacement for the qualification. According to the current rules the top 6 engines of the Swiss event, not including those that are already included in one of the leagues, will play in the initial league stage. This season there were many engines from the last season that did not participate, either by the developer choice or since they are not in development any more. This included premier division participants Berserk and Koivisto. As a result almost all the engines that played in the Swiss event continued to the leagues. </p><p>The first league event was the <a href="https://mytcecexperience.blogspot.com/2023/08/season-25-entrance-league.html">entrance league</a>, including 16 engines of which 5 were new to TCEC. The four engines that advanced were all new: Viridithas, Clover, DeepSjeng and Caissa. Caissa managed to secure 4th place despite a bug that caused it to crash on time twice, Booot finished a close 5th. In <a href="https://mytcecexperience.blogspot.com/2023/08/season-25-league-2.html">league 2</a> the same 4 engines continued their journey and advanced again, in a different order. Caissa's bug was fixed and it finished 2nd, DeepSjeng and Arasan battled for 4th place and only a win in a direct encounter in the last rounds ensured that DeepSjeng would advance. <a href="https://mytcecexperience.blogspot.com/2023/08/season-25-league-1.html">League 1</a> was a different story for the 4 newcomers, none were strong enough to advance a third time. RubiChess dominated the league and finished in 1st place. rofChade was in 2nd place at the half way point, with Igel a close 3rd. In the last RR Igel managed to move ahead of rofChade and in the end it was Igel that advanced, despite losing two games to rofChade in the league.</p><p>The <a href="https://mytcecexperience.blogspot.com/2023/10/season-25-premier-division-final-results.html">premier division</a> was a month long 6-DRR event. The top3 engines, Stockfish, Leela and KomodoDragon were still dominant as in the previous several seasons, but this season there were greater score gaps between them. In the 90 top3-bottom5 game pairs the top3 did not lose a single game pair, and drew only 17. Stockfish finished first with no game pair loss at all, beating Leela 3 times and KomodoDragon 5 times. Leela beat KomodoDragon once, but it won 5 more game pairs than KomodoDragon against the bottom5 engines and finished 2nd. The top3 standings were obvious quite early in the division, the main race that was interesting was between Ethereal and RubiChess for 4th place that led to the division playoff stage. Ethereal and RubiChess were very close to one another from the start, each had one head to head game pair win in the first DRRs. After 5 DRRs Ethereal managed to lead RubiChess by 1.5 points. Then in the last DRR Ethereal unexpectedly lost a game pair to Igel, RubiChess also beat Ethereal in their final direct encounter game pair and this secured 4th place for RubiChess.</p><p>TBD - season summary: premier division playoff, personal</p><p>Games 91-92 started with a sideline in the QGA, Alekhine defense. The white queen was out on the queen side and a black rook was on a7 protecting the b7 pawn. In <a href="https://tcec-chess.com/#div=sf&game=91&season=25">game 91</a> the engines opened files on the queen side and Stockfish castled short. There were many early piece exchanges, the game reached a QRN vs QRN position with white a pawn up on move 23. Stockfish moves its queen forward and Leela exchanged queens.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjGw4jWHhAzCezNKZ-hY9sBvA6ZJvuQw4l1ank3_sUJiNISwu3IcrBHokc90aJhgGGNK8GggQojdSXmlLEmwcHlzJ-5T3_PJF5vY6DsaoaMl_t2KH75IlKmWY6xmE8tVCxqTq2sAJeJ660rQOGCQ3bt8inYI9WqV9ITuGbLg1jjjgyB9lvexhzUez6HBSQ/s1168/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="694" data-original-width="1168" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjGw4jWHhAzCezNKZ-hY9sBvA6ZJvuQw4l1ank3_sUJiNISwu3IcrBHokc90aJhgGGNK8GggQojdSXmlLEmwcHlzJ-5T3_PJF5vY6DsaoaMl_t2KH75IlKmWY6xmE8tVCxqTq2sAJeJ660rQOGCQ3bt8inYI9WqV9ITuGbLg1jjjgyB9lvexhzUez6HBSQ/w640-h380/pic1.jpg" width="640" /></a></div><p>A pawn advantage with all pawns on the same side was small but significant, evals increased slowly. When it could Leela exchanged pawns while keeping its pieces on the board. On move 57 Leela created a passer in the center, on move 60 it connected a second passer while giving Stockfish a passer on the king side. </p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhhvcvr1huuzjtuZoeQDELT-jbB7QMGPw0JdDgDOKJz24XpU3kSr9PfnT3icVZdvQ10ZuikGXOb7sZ0_EbrrASn-Y8gnEqSsqLu3CVMsOgfqhqxa6IxZib3bq7dIrIafzLIAFRLc6qJ9PTCmfEoEC7RiNu2OkHKIG69co-deP-AlpErV8oeyxw-aBPKRyA/s1165/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="691" data-original-width="1165" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhhvcvr1huuzjtuZoeQDELT-jbB7QMGPw0JdDgDOKJz24XpU3kSr9PfnT3icVZdvQ10ZuikGXOb7sZ0_EbrrASn-Y8gnEqSsqLu3CVMsOgfqhqxa6IxZib3bq7dIrIafzLIAFRLc6qJ9PTCmfEoEC7RiNu2OkHKIG69co-deP-AlpErV8oeyxw-aBPKRyA/w640-h380/pic2.jpg" width="640" /></a></p><p>Leela pushed its passers forward and Stockfish couldn't stop them. Leela gave a knight to queen one passer and mated. </p><p>In <a href="https://tcec-chess.com/#div=sf&game=92&season=25">game 92</a> the engines repeated game 91 for 16 plies with transposition, opening files on the queen side. Stockfish went a pawn up but all pieces stayed longer on the board. On move 27 the engines exchanged knight for bishop, the first pieces off the board. By move 32 all rooks were exchanged.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg1VY0ibyJHqoOFmGQDWRCGyT8RScbpdIZvbaWcOxODnHoz6bv2jmmP7MbiSbMcOS_xM4bmBUYAIOWz1-DhEDcRNVeFZfr0OxwJhGnSrLtJDW_RNRTMFwNB0pC7xSGMNHGPWq60dR1Jhf5P8os6Qn0metQbmlpKfvuCEH-CzulwvKtCA8MxSR40q0f6xd4/s1177/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="691" data-original-width="1177" height="376" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg1VY0ibyJHqoOFmGQDWRCGyT8RScbpdIZvbaWcOxODnHoz6bv2jmmP7MbiSbMcOS_xM4bmBUYAIOWz1-DhEDcRNVeFZfr0OxwJhGnSrLtJDW_RNRTMFwNB0pC7xSGMNHGPWq60dR1Jhf5P8os6Qn0metQbmlpKfvuCEH-CzulwvKtCA8MxSR40q0f6xd4/w640-h376/pic1.jpg" width="640" /></a></div><p>Leela avoided exchanging queens, Stockfish's eval started to increase as it pushed pawns in the center. In a complex position Leela chose to give a knight for 3 pawns and expose the white king. On move 47 Stockfish saw a win from far away, the engines reduced to a QBB vs QB position.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgmXHomV5UiKle6dFsNz15xo1c_eTf22fpCXeE0m7Scs-0r1xOx4ybPo396F8Aa1OeVBk1pbyKTB610yq0F33QgJuGbn64pF3clW60salwUm7JfLRvBestOEJsM0ABqoyyPRifCrL61jeCMLOiQWdtH0k50apZercXe9j1uyYchHNbyuRt658zw70hdDg8/s1174/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="694" data-original-width="1174" height="378" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgmXHomV5UiKle6dFsNz15xo1c_eTf22fpCXeE0m7Scs-0r1xOx4ybPo396F8Aa1OeVBk1pbyKTB610yq0F33QgJuGbn64pF3clW60salwUm7JfLRvBestOEJsM0ABqoyyPRifCrL61jeCMLOiQWdtH0k50apZercXe9j1uyYchHNbyuRt658zw70hdDg8/w640-h378/pic2.jpg" width="640" /></a></p><p>Leela gave many checks with its queen and captured the last white pawn. Stockfish found safety for its king in the center with the pieces blocking the black queen. It captured two black pawns and slowly improved its eval though it was hard to understand on the board. The white pieces slowly closed in on the black king, Stockfish had mate in its PV when Leela gave its queen and the game ended in a tablebase win. There were two white wins in this game pair, Stockfish leads 25-20.</p><p>Games 93-94 started with the Sicilian Lowenthal variation, played in high level human chess. In <a href="https://tcec-chess.com/#div=sf&game=93&season=25">game 93</a> the engines castled in opposite directions. There was a long PV agreement and many early exchanges, the game reached a QRR vs QRR position on move 23. Evals started to increase, after exchanging queens Leela captured a pawn.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjA-17n1uibZqy5M_P9n1EyMwSPrYeI6C0jr9CM58iQn2k84kRv2Ykb8o4r24nmLJVD9Rwvr3W48hRO2cBl4iiGMn0xkegCL2zxAzp-OQYSgmy8hqvZgYxE1ftJqMjKPviKYVKR9vWcczVHe-lz9dcApOzvzocySD6j1t3YqOjrAqBpVZkvVLaJrJJTgHw/s1171/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="694" data-original-width="1171" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjA-17n1uibZqy5M_P9n1EyMwSPrYeI6C0jr9CM58iQn2k84kRv2Ykb8o4r24nmLJVD9Rwvr3W48hRO2cBl4iiGMn0xkegCL2zxAzp-OQYSgmy8hqvZgYxE1ftJqMjKPviKYVKR9vWcczVHe-lz9dcApOzvzocySD6j1t3YqOjrAqBpVZkvVLaJrJJTgHw/w640-h380/pic1.jpg" width="640" /></a></div><p>Stockfish had a passer in the center while Leela had a pawn majority on the queen side. Leela captured a pawn on the queen side, the black king moved forward to support the passer. Leela captured the second black pawn on the queen side, creating 3 connected passers. It blocked the black passer and pushed its own forward. Stockfish lost material trying to stop the white passers, Leela queened and mated.</p><p>In <a href="https://tcec-chess.com/#div=sf&game=94&season=25">game 94</a> the engines repeated game 93 for 21 plies, Leela chose a different defense and Stockfish's eval started to increase. Again the game reached a double rook ending on move 29, this time material was equal but Stockfish had doubled rooks on the g file, blocking and threatening the black king on the open h file.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg2tWTj4XSYlq80NiWE0pq497MuX1NPovx_RiJD55CeUIVNhsn0dz2EzgrUEVsI8xWEDnYjdM_Otkyxr6DfIY3V3nfZ07oTbGnIYtkiAL9koY1tUYz__jFVnak86h3LzkVEMllCcfGUWMdqbcTJa9YXNGVZBDYDqPBfZzEspeUzJJIiWr8oK1yAysVXIKw/s1188/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="693" data-original-width="1188" height="374" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg2tWTj4XSYlq80NiWE0pq497MuX1NPovx_RiJD55CeUIVNhsn0dz2EzgrUEVsI8xWEDnYjdM_Otkyxr6DfIY3V3nfZ07oTbGnIYtkiAL9koY1tUYz__jFVnak86h3LzkVEMllCcfGUWMdqbcTJa9YXNGVZBDYDqPBfZzEspeUzJJIiWr8oK1yAysVXIKw/w640-h374/pic1.jpg" width="640" /></a></div><p>Leela's eval was stable for a long time, Stockfish wasn't in a hurry with repeating checks every few moves. The engines exchanged a pair of pawns and Leela created a passer. The passer was isolated and had to be protected. There was a threat of mate that Leela had to deal with as well. On move 58 Leela's eval jumped after a long think, Stockfish forced a small but significant change in the black rooks' placement. </p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh0ipb9Eg-iLax0IkVAeDd67HQssQy-2SbZ11RXRUBCAO91XlRZbUQihZ5muKR8xDGRvlv8JJPK16BWl_ZT0zVQSmmhH2X_20FN3pS5G2WWC6Ochu2bb3N2FnBp1N9gBd_YMaGgngcHMYpp5NF3wrWE56_g1ZRNNBTvVzpHH0JUP88WsvNX1-OjTB6VclM/s1180/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="693" data-original-width="1180" height="376" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh0ipb9Eg-iLax0IkVAeDd67HQssQy-2SbZ11RXRUBCAO91XlRZbUQihZ5muKR8xDGRvlv8JJPK16BWl_ZT0zVQSmmhH2X_20FN3pS5G2WWC6Ochu2bb3N2FnBp1N9gBd_YMaGgngcHMYpp5NF3wrWE56_g1ZRNNBTvVzpHH0JUP88WsvNX1-OjTB6VclM/w640-h376/pic2.jpg" width="640" /></a></p><p>The white king managed to move forward to the center to block the passer. The queen side pawns stabilized, after many check repeats Stockfish exchanged a pair of rooks on move 82. Material was still equal, the engines traded pawns and both had only two pawns on the queen side. However, the black king was far on the king side and unable to help. Stockfish moved its king behind the black pawns and the game ended in a tablebase win. There were two white wins in this game pair, Stockfish leads 26-21.</p><p>Games 95-96 started with a 24-ply line in the French Winawer, retreat variation. The white queen captured two pawns on the king side and the black queen captured a pawn on the queen side. In <a href="https://tcec-chess.com/#div=sf&game=95&season=25">game 95</a> the engines exchanged minor pieces after the start, Stockfish castled long and Leela moved its king forward without castling. Evals started to increase as Leela captured another pawn on the king side, Stockfish chased the white queen away and pushed the e pawn forward. As a result the e pawn became an advanced passer, while Leela had 3 connected passers on the king side. Stockfish captured a pawn and created a passer on the queen side, on move 31 the engines exchanged queens and the game reached a RRB vs RRN position.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjR-C4-eEm9oyqKJ4HINsnjzYVeOGqvg40Jm-J_RkmPVvy2b54XH7hUsX63gWUDpQ4hdNQlaDghpTl1t66MIKe6QUu6ZqQoD6Iho67xrEWxF4pQN8Klp4EOON3Tkk9j9398U6QOumYOtdOkq5a-hQtkY45LbJVupECfX9W3-YKPFDnUUwOKRHZfC2hYdxI/s1162/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="691" data-original-width="1162" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjR-C4-eEm9oyqKJ4HINsnjzYVeOGqvg40Jm-J_RkmPVvy2b54XH7hUsX63gWUDpQ4hdNQlaDghpTl1t66MIKe6QUu6ZqQoD6Iho67xrEWxF4pQN8Klp4EOON3Tkk9j9398U6QOumYOtdOkq5a-hQtkY45LbJVupECfX9W3-YKPFDnUUwOKRHZfC2hYdxI/w640-h380/pic1.jpg" width="640" /></a></div><p>Leela blocked the black passers with two pieces and slowly pushed its passers on the king side. The two black passers were stopped on the 2nd rank, Stockfish used its rooks to try to stop the white passers but Leela managed to queen one. Stockfish lost material and was mated.</p><p>In game 96 both engines castled long, Stockfish shifted its queen to the queen side. Stockfish pushed a passer on the king side but without support it stopped on the 5th rank. The engines mostly shuffled and evals came down, Stockfish gave a rook for a bishop and pushed the passer to the 7th rank. The engines traded RB for Q, Leela captured the passer, evals were low and the game was adjudicated. Leela wins the game pair, Stockfish leads 26-22.</p><p>Games 97-98 started with a sideline of the Indian defense, Wade-Tartakower variation. In game 97 Leela castled long, there were a few minor piece exchanges and Stockfish also castled long. The engines shuffled for a while and evals came down, then they exchanged a pair of rooks and reduced to a QRB vs QRN position. Leela captured a pawn and created a passer, Stockfish regained the pawn later. After exchanging queens evals were low and the game was adjudicated. In game 98 Stockfish castled long and Leela chose to castle short after the white queen captured the b7 pawn. Stockfish pushed pawns on the king side and Leela blocked them. Evals came down and the game reached a RRB vs RRN position. After exchanging a pair of rooks the game was adjudicated.</p><p>Games 99-100 started with a rare 22-ply sideline of the Caro-Kann, Panov attack. In <a href="https://tcec-chess.com/#div=sf&game=99&season=25">game 99</a> there were no exchanges after the start, both engines placed their major pieces on the center files. After a knight exchange on move 22 Stockfish created a passer in the center. The engines shuffled for a while, then Leela created a passer in the center after a pawn exchange on move 35. On move 43 Leela captured the black passer and exchanged bishops.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiJkSPa8yFFAhGfltT4lkcaRXVVGDjNPzEdZxdq8TpAGROgBV6zjHm_l2QhrMsSkx_X0oe7nDhn4mWsbO2j3eeQvgQIJRv7DRUbdYjUohRtQ_Atgc83AFqsWkTWr7r11EFCP6nIytc0FCQvRZNGMuaPnbV5QhFAcjZwS_8Y8YbJzy8oYVvfD19uLQbaNPE/s1168/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="693" data-original-width="1168" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiJkSPa8yFFAhGfltT4lkcaRXVVGDjNPzEdZxdq8TpAGROgBV6zjHm_l2QhrMsSkx_X0oe7nDhn4mWsbO2j3eeQvgQIJRv7DRUbdYjUohRtQ_Atgc83AFqsWkTWr7r11EFCP6nIytc0FCQvRZNGMuaPnbV5QhFAcjZwS_8Y8YbJzy8oYVvfD19uLQbaNPE/w640-h380/pic1.jpg" width="640" /></a></div><p>Evals increased as the engines stabilized the pawns on the king side. Leela exchanged a pair of pawns on the queen side and then the engines started to shuffle. Evals drifted down as the 50-move counter got close to 0, Leela saw exchanges in its PV but Stockfish decided to initiate a queen exchange. Evals increased quickly, on move 106 the game reached a RB vs RB position.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiYSGoV8_uu5lM-WY115Bjh_RTyM4ix0JZPhrgTiSHahdeJLwB7skzgnbSHBCpSppDG7GcZsWA5aPHWzEPXtQHpCxmAeKrlfX9mPnNXsDrWySlHpBiOasBfsHY-mMrg0KcgQ6IuCcE82L2CB0FRgYxexsFE55-XgPrahlTKbpBtUhhLN28mUUrXKTYKc8w/s1165/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="687" data-original-width="1165" height="378" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiYSGoV8_uu5lM-WY115Bjh_RTyM4ix0JZPhrgTiSHahdeJLwB7skzgnbSHBCpSppDG7GcZsWA5aPHWzEPXtQHpCxmAeKrlfX9mPnNXsDrWySlHpBiOasBfsHY-mMrg0KcgQ6IuCcE82L2CB0FRgYxexsFE55-XgPrahlTKbpBtUhhLN28mUUrXKTYKc8w/w640-h378/pic2.jpg" width="640" /></a></p><p>Stockfish tried to stop the center passer and Leela captured the two black pawns on the king side. Stockfish couldn't avoid a queening followed by mate.</p><p>In <a href="https://tcec-chess.com/#div=sf&game=100&season=25">game 100</a> both engines concentrated their pieces in the center, the exchanges started on move 18. Stockfish pushed the h pawn to h6 and exchanged it, on move 26 the game reached a QBB vs QBB position.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiDyj4D_xPGdl5C8Iut1X-6ooQGyqHMhyqXTu_vKsdKutDKcX_2cMM6YcAjGmv0QKFFNeCtcOAhUFeXCJTR1ke8vKLutYb6FjXZPr94_qYqhZd4pP1B9McvHlgodQfLYC7YicycJc1zMV781aTk2il96Ap7PiIKjTbjb5RvxkCYH0wUZJCbHd0zM67QmMQ/s1171/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="694" data-original-width="1171" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiDyj4D_xPGdl5C8Iut1X-6ooQGyqHMhyqXTu_vKsdKutDKcX_2cMM6YcAjGmv0QKFFNeCtcOAhUFeXCJTR1ke8vKLutYb6FjXZPr94_qYqhZd4pP1B9McvHlgodQfLYC7YicycJc1zMV781aTk2il96Ap7PiIKjTbjb5RvxkCYH0wUZJCbHd0zM67QmMQ/w640-h380/pic1.jpg" width="640" /></a></div><p>Stockfish's eval slowly increased but there were no exchanges except a pair of pawns on the queen side. The black king hid in the corner protected by the black queen and it seemed that Stockfish was shuffling. Slowly Leela's eval increased as well, Stockfish moved its king to the center and pushed the king side pawns. </p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgqqDPy_Q5loUEhrTlF03aj6wzixF039o5g3Yiz3xUIrfhb2SNJbxygAJmBW6djGCeVrpccwMVhEwgAk3IZri4uNuIgy8zlXJei9S11TUjY7SgVEtHnPS1m-C35-WLpJ9jwBwdK7fXaf20IzsQ_GtCd8F2Klfx24P6FPj4QLkIMhcxYPtgevZign4380w8/s1183/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="697" data-original-width="1183" height="378" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgqqDPy_Q5loUEhrTlF03aj6wzixF039o5g3Yiz3xUIrfhb2SNJbxygAJmBW6djGCeVrpccwMVhEwgAk3IZri4uNuIgy8zlXJei9S11TUjY7SgVEtHnPS1m-C35-WLpJ9jwBwdK7fXaf20IzsQ_GtCd8F2Klfx24P6FPj4QLkIMhcxYPtgevZign4380w8/w640-h378/pic2.jpg" width="640" /></a></p><p>Leela had to defend its weak a5 and h7 pawns, and the possibility of a pawn attack on the king side. In the end Stockfish found a way to attack from the queen side, it exchanged a pair of bishops and saw the win in its PV. Stockfish reduced to a queen ending two pawns up. The white king moved forward, Leela lost its queen, Stockfish queened a passer and mated. There were two white wins in this game pair, Stockfish leads 27-23.</p><p><br /></p>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com0tag:blogger.com,1999:blog-4430065842059358622.post-68571096835893987212023-10-30T01:08:00.000+02:002023-10-30T01:08:24.006+02:00Season 25 superfinal games 81-90<p>After 90 games Stockfish leads 24-19 with 47 draws. Leela won another game pair and Stockfish's lead is down to 5 wins. There were 4 drawn game pairs, in one of these there were two white wins. Stockfish hasn't won a game pair in the last 13 played, while Leela won 3. There are only 5 game pairs to go so Stockfish is the favorite to win the match, but Leela is still fighting.</p><p>Games 81-82 started with a 22-ply rare sideline in the KID, Petrosian variation. All pieces and pawns were on the board and the center was blocked. In game 81 the engines pushed pawns across the board, Stockfish gave a pawn and opened a hole in the pawn line on the king side. Stockfish placed a knight on f5 and Leela moved its king to the corner. Evals came down and there was a long series of exchanges that opened the center and queen side. The result was that Stockfish was down a knight for a pawn with connected passers on the king side. After some shuffling Stockfish gave a rook and a bishop and queened a passer. The game ended in check repetition. In game 82 the engines opened the f file and the a file, then exchanged a pair of rooks. Evals came down, after exchanging a pair of bishops the engines started to shuffle. On move 40 Leela pushed the g pawn forward until Stockfish captured it. The engines reduced to a QB vs QN position, evals were low and the game was adjudicated.</p><p>Games 83-84 started with a rare sideline in the KID Fianchetto variation. In <a href="https://tcec-chess.com/#div=sf&game=83&season=25">game 83</a> the engines blocked the center, Stockfish opened the queen side and Leela pushed pawns on the king side. The white king walked to the king side without castling. Stockfish had two strong knights in the center, it placed its major pieces on half open files on both sides. However evals slowly increased. Leela pushed a pawn to h6, then captured a pawn and created a passer on the queen side.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjINfr3CaajRhrzhM7kgTR3TEW0KJri0KjIrkmgP73zac40szXyhyBdtC5YGKOw5KoVbaODCjuk-bVrYnLo0-cC0rB3pqpr7iSjePXqh-WRrmAy1KVEIUJT2blqwbg2EUUBcHPADXi_OpvXEI_0aUnpV64mynA9G6DkUlmxuVRXx0IlaiusqzduwQZPGCk/s1165/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="694" data-original-width="1165" height="382" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjINfr3CaajRhrzhM7kgTR3TEW0KJri0KjIrkmgP73zac40szXyhyBdtC5YGKOw5KoVbaODCjuk-bVrYnLo0-cC0rB3pqpr7iSjePXqh-WRrmAy1KVEIUJT2blqwbg2EUUBcHPADXi_OpvXEI_0aUnpV64mynA9G6DkUlmxuVRXx0IlaiusqzduwQZPGCk/w640-h382/pic1.jpg" width="640" /></a></div><p>Leela exchanged a pair of knights, its passer shifted to the b file. With rook support Leela pushed the passer to the 5th rank where it was blocked. Stockfish doubled rooks on the f file, attacking the f3 pawn and trying to prevent it from moving forward. Leela captured one rook for a bishop, then threatened the back rank from the open c file. Stockfish blocked the c file and opened the way for the white passer to advance. Stockfish was desperate, it gave the second rook for a bishop to block the f pawn.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiHLQEdoFzctudz4HMtEUXDKm68oKK2ci1WSOc_LI_wYEZj2B5n80dil9FcBdPc8j1Gnu2HgmUZ0h2x3lZj6c_ZPXQ4u4IFshGD2AqYQ0Qm9XgSEgaFY6wb8kZdoBMk5m1c06Xj_nn4Z3WxiBnPAZYscsAaweVj2lxkfwWhSkofki6_x4kcURAqz2UiAIU/s1167/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="696" data-original-width="1167" height="382" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiHLQEdoFzctudz4HMtEUXDKm68oKK2ci1WSOc_LI_wYEZj2B5n80dil9FcBdPc8j1Gnu2HgmUZ0h2x3lZj6c_ZPXQ4u4IFshGD2AqYQ0Qm9XgSEgaFY6wb8kZdoBMk5m1c06Xj_nn4Z3WxiBnPAZYscsAaweVj2lxkfwWhSkofki6_x4kcURAqz2UiAIU/w640-h382/pic2.jpg" width="640" /></a></p><p>Stockfish quickly lost more material, Leela queened and mated.</p><p>In game 84 the engines blocked the center but there were no pawn exchanges after the start, only a few minor piece exchanges. Stockfish walked its king to the queen side, all files were blocked except the b and f files and the engines started to shuffle. Leela's eval dropped to 0, Stockfish couldn't find any safe way to move past the pawn lines. Pawn moves and captures reset the 50-move counter on moves 36, 83, 128, 175 (Stockfish gave a pawn), 204, 252 (Leela gave a pawn), 301 (knight exchange), 310 (Stockfish gave a pawn), and 329. The game finally ended on move 379 in a 50-move draw, after approximately 350 moves of nothing. This is a new TCEC record for most moves in a game. Leela wins the game pair, Stockfish leads 23-18.</p><p>Games 85-86 started with one of the main lines in the Czech Benoni defense, the center was blocked and all pieces and pawns were on the board. In game 85 there was one pawn exchange on the king side and Leela's eval started to increase. Stockfish captured a pawn, the engines played a long PV agreement and Leela's eval slowly came down. Stockfish gave back the pawn and Leela went a pawn up, then in a series of exchanges the engines reduced to a same color bishop ending. Leela wouldn't lower its eval for a long time, the engines shuffled and exchanged a few pawns. The game was adjudicated on move 118. In game 86 there were no exchanges after the start, the engines exchanged a pair of knights and mostly shuffled behind their pawn lines. On move 43 the engines exchanged a pair of bishops, then Stockfish captured a pawn but there was a stable pawn wall across the board. The engines shuffled for a long time, the 50-move counter was reset on moves 98 (knight for rook trade), 143, 182 (Stockfish gave a pawn), 224 (Stockfish gave another pawn), 233, 247 (queen exchange). On move 297 the game finally ended in a 50-move draw. Another long game with nothing happening.</p><p>Games 87-88 started with a rare sideline of the English symmetrical variation. In <a href="https://tcec-chess.com/#div=sf&game=87&season=25">game 87</a> Stockfish exchanged minor pieces and its queen moved forward on the queen side. Stockfish captured two pawns and created 3 connected passers. Leela captured one passer and pushed its center pawns, Stockfish gave a rook for a bishop to protect its king. Stockfish pushed its passers forward, after exchanging queens the game reached a RB vs BN position on move 38.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiDjsoA1zVFBwZfec8B4bXRwxbm2JI8vf6JKQAkK06vn4Yu30yvH79Wej9snexym__lnlsjmYN9LgIjOLJKLkm18tGyuz-2q1owq-XaVZ-Kf5XaZhNL0KXI1YotOWsNYVz3-WKElzDf4btOLAVIC0xQNbh-tePgFrt9deYVOHjfd2dXjbarsooMxBKAVxA/s1168/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="694" data-original-width="1168" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiDjsoA1zVFBwZfec8B4bXRwxbm2JI8vf6JKQAkK06vn4Yu30yvH79Wej9snexym__lnlsjmYN9LgIjOLJKLkm18tGyuz-2q1owq-XaVZ-Kf5XaZhNL0KXI1YotOWsNYVz3-WKElzDf4btOLAVIC0xQNbh-tePgFrt9deYVOHjfd2dXjbarsooMxBKAVxA/w640-h380/pic1.jpg" width="640" /></a></div><p>Stockfish gave up the d and h pawns quickly, but it protected the others and Leela had a hard time trying to improve. The engines shuffled and evals drifted down. On move 65 Leela exchanged a pair of pawns on the king side, Stockfish's eval jumped.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh7BptaNck1pA_ahEhpfpy5E-UTlKV3kyUQBc6i77rFICmGPGLeLyeiXahJu9Z_2dkYxae2j3wkh-MgK4ykEc8VFSwlEjwsU5YHw1ltJj1plIuuceVK15aV84go5RHQzdKpK47iykvJ_pLccjkucvMd7U5KXl2_7SxF4SZ5Vp8uovo2URioGE0MZYUIZ1k/s1161/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="694" data-original-width="1161" height="382" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh7BptaNck1pA_ahEhpfpy5E-UTlKV3kyUQBc6i77rFICmGPGLeLyeiXahJu9Z_2dkYxae2j3wkh-MgK4ykEc8VFSwlEjwsU5YHw1ltJj1plIuuceVK15aV84go5RHQzdKpK47iykvJ_pLccjkucvMd7U5KXl2_7SxF4SZ5Vp8uovo2URioGE0MZYUIZ1k/w640-h382/pic2.jpg" width="640" /></a></p><p>The game was far from over but evals started to increase. Leela slowly moved its king to the center. The black king moved to the queen side and on move 85 Leela captured the black e pawn. The white f pawns became doubled passers, Leela slowly pushed them forward. Eventually Leela queened and the game ended in a tablebase win on move 121.</p><p>In <a href="https://tcec-chess.com/#div=sf&game=88&season=25">game 88</a> the engines repeated game 87 for 20 plies, Leela captured one pawn on the queen side but Stockfish protected the second one. Stockfish regained the pawn and exchanged a pair of rooks, its eval started to increase. Leela captured the second pawn on the queen side and created two passers there but Stockfish captured one of them. After exchanging queens Stockfish gave a rook for two minors and reduced to a BB vs R ending. </p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi3FepaKaCSj6Buq6xqYskdTKpOgXDjiV-6-i4iQtfSQ4bol2LvSO4CpfPYieWqxIdBqT3TgCclhcsJe8tv3OfFsenDEyrx69MXtsVe2HOBEv6kIu0VVZdiTDRtdzjTLRRrOlaRmkylj1GhmJnDTOmrzEJdEKjLQSwGtMCPzaVaCP1YkDyO5uLTQm2Civg/s1173/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="691" data-original-width="1173" height="378" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi3FepaKaCSj6Buq6xqYskdTKpOgXDjiV-6-i4iQtfSQ4bol2LvSO4CpfPYieWqxIdBqT3TgCclhcsJe8tv3OfFsenDEyrx69MXtsVe2HOBEv6kIu0VVZdiTDRtdzjTLRRrOlaRmkylj1GhmJnDTOmrzEJdEKjLQSwGtMCPzaVaCP1YkDyO5uLTQm2Civg/w640-h378/pic1.jpg" width="640" /></a></div><p>Stockfish exchanged a pair of pawns on the king side and created a 3 vs 1 pawn majority in the center. Its eval showed a clear win while Leela's eval increased very slowly. Leela pushed its passer and eventually captured a bishop for it. Stockfish slowly pushed the pawns forward, making sure the black rook couldn't stop them. It finally queened a passer on move 81, mating a few moves later. There were two white wins in this game pair, Stockfish leads 24-19.</p><p>Games 89-90 started with a 24-ply rare sideline in the Benoni classical variation, Czerniak defense. In game 89 after one move the engines started to play out a very long PV agreement. Stockfish gave a bishop and opened files on the king side. There was a threat to the white king, Leela gave back the piece and reduced to a RN vs RB position with white a pawn up. Stockfish's eval dropped, the engines traded pawns and then the rooks were exchanged. Leela wouldn't lower its eval for a long time, the game was adjudicated on move 92. Game 90 started with a 30-ply repeat of game 89. The game reached the same RN vs RB position, the engines traded pawns and Leela lowered its eval for an early adjudication on move 49.</p><p><br /></p>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com0tag:blogger.com,1999:blog-4430065842059358622.post-23603181978859207062023-10-28T12:25:00.000+03:002023-10-28T12:25:37.119+03:00Season 25 superfinal games 71-80<p>After 80 games Stockfish leads 23-17 with 40 draws. Leela won a game pair and reduced Stockfish's lead to 6 wins. The other game pairs were draws, with 3 having two white wins. Stockfish hasn't won a game pair for 8 straight pairs played, while losing 2. There is still hope for Leela, though it may be too late since there are only 10 game pairs left in the match.</p><p>Games 71-72 started with a rare sideline in the Nimzo-Dutch, Alekhine variation. In <a href="https://tcec-chess.com/#div=sf&game=71&season=25">game 71</a> there were a few minor piece exchanges and the engines opened the d file. Stockfish gave a pawn, the engines exchanged a pair of rooks and evals were mostly stable. On move 28 the engines opened the a file.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhuDM5pKSuUt5yDh6Ac65zK5ivdZxz-kIYtgIAqfd7quGIM563cciaFxT29tRlgQJ2IpY-3V7fyHxvJVU4jD0HAXLo2fupVjMMEfLjwqF4c837YXtgGgDOLR0JRwYXRUdkFe5H13wQJpkZ0BObLxQ4GezOICOUmzEsTCWZmtjPh5YmI7zLc6iUeP75pw-4/s1164/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="691" data-original-width="1164" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhuDM5pKSuUt5yDh6Ac65zK5ivdZxz-kIYtgIAqfd7quGIM563cciaFxT29tRlgQJ2IpY-3V7fyHxvJVU4jD0HAXLo2fupVjMMEfLjwqF4c837YXtgGgDOLR0JRwYXRUdkFe5H13wQJpkZ0BObLxQ4GezOICOUmzEsTCWZmtjPh5YmI7zLc6iUeP75pw-4/w640-h380/pic1.jpg" width="640" /></a></div><p>Evals started to increase though the engines seemed to be shuffling. Leela gave two pawns on the queen side and captured a rook for a bishop. Leela then captured the two black pawns on the queen side, it was a pawn up in a QRB vs QBN position and evals were high.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi1uGwQrOEu7Q7lehCuBj_7gXgLRZKhI-5h14XyekUTAKlohIhX7T1T8altJmQu8aj7602f3IbhGh9-EQJAqyamN5Z5FIJLT5TVF_yV20M4C_76c1hXJ-H3pFltIdLgnfAFTPj92P_FG2GmlgU6L4HayhvfLbEJvT-g3CAjowZYsLo7WrKUBiP0gREX4KY/s1168/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="694" data-original-width="1168" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi1uGwQrOEu7Q7lehCuBj_7gXgLRZKhI-5h14XyekUTAKlohIhX7T1T8altJmQu8aj7602f3IbhGh9-EQJAqyamN5Z5FIJLT5TVF_yV20M4C_76c1hXJ-H3pFltIdLgnfAFTPj92P_FG2GmlgU6L4HayhvfLbEJvT-g3CAjowZYsLo7WrKUBiP0gREX4KY/w640-h380/pic2.jpg" width="640" /></a></p><p>Stockfish tried to avoid exchanges, Leela pushed the h pawn and it became a passer. Stockfish lost a bishop and captured the passer, it saw mate in its PV. Leela took a longer route, in the end a series of exchanges resulted in a tablebase win.</p><p>In game 72 more pieces stayed on the board, a pawn exchange opened the a file and evals came down. After some shuffling the engines opened the queen side and Stockfish went a pawn up. Stockfish traded its queen for a rook and a bishop, the engines reduced to a RBN vs QN position with white a pawn up. After 20 moves the engines traded minor pieces, when evals were low enough the game was adjudicated. Leela wins the game pair, Stockfish leads 20-14.</p><p>Games 73-74 started with a rare sideline in the Old Indian defense, normal variation. In <a href="https://tcec-chess.com/#div=sf&game=73&season=25">game 73</a> the engines locked the center and there were no exchanges after the start. Leela offered a bishop and Stockfish refused to weaken its king. The engines opened the c file and exchanged a pair of knights, Leela captured the g7 pawn, then Stockfish captured two pawns on the king side. The black king looked vulerable, Stockfish exchanged queens and evals started to increase. The game reached a RRB vs RRB position on move 40.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgvTVaYqBTMBZQ_n6AUVwhvcyIBB463DK8UwpNVHSoblYnAu0ltits2CRpX1RnvgAiC6NAbK8qPGhg3WzEI_DeXtvCLxIUPbIE4GjpHLbcDgCxQClUYDDaImsX1WtmzgT8SHOX6RuRz1nO1tjE_Kq22UjdFPeW_BLaqC-BrUVHjm2M8vB5L2VrBrA_kUw8/s1168/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="690" data-original-width="1168" height="378" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgvTVaYqBTMBZQ_n6AUVwhvcyIBB463DK8UwpNVHSoblYnAu0ltits2CRpX1RnvgAiC6NAbK8qPGhg3WzEI_DeXtvCLxIUPbIE4GjpHLbcDgCxQClUYDDaImsX1WtmzgT8SHOX6RuRz1nO1tjE_Kq22UjdFPeW_BLaqC-BrUVHjm2M8vB5L2VrBrA_kUw8/w640-h378/pic1.jpg" width="640" /></a></div><p>After a pawn exchange on the queen side all the black pawns were isolated. Leela protected its d5 pawn with the bishop and started capturing black pawns. Stockfish held on to its a pawn, Leela pushed passers and moved its king forward. Stockfish lost material trying to stop the passers, the game ended in a tablebase win.</p><p>In <a href="https://tcec-chess.com/#div=sf&game=74&season=25">game 74</a> there was one pair of pawns exchanged after the start, all files remained closed. The engines mostly shuffled behind their pawn lines but evals slowly increased. A pawn exchange on move 32 created passers in the center for both engines, on move 35 the first minor pieces were exchanged. Stockfish captured the doubled black passers in the center by move 42.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj6o8n2gKd2BiLB5-v7cDwurL8ImQH4WdjbY1pwJBnFJBnykTT1Qhu7mj7qsxX0YLpq1tSEp09-xOYCeS3rqmuOdjyRqR0guBn2-XL-cRtNClPcDYRoe0DnDY32W_U3YMv-WcZFanRvXe73FXJYXgnj9z5C6JC_qJ0L2JA_bzTPMRZG8lz0V-BLcuXe13Y/s1171/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="694" data-original-width="1171" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj6o8n2gKd2BiLB5-v7cDwurL8ImQH4WdjbY1pwJBnFJBnykTT1Qhu7mj7qsxX0YLpq1tSEp09-xOYCeS3rqmuOdjyRqR0guBn2-XL-cRtNClPcDYRoe0DnDY32W_U3YMv-WcZFanRvXe73FXJYXgnj9z5C6JC_qJ0L2JA_bzTPMRZG8lz0V-BLcuXe13Y/w640-h380/pic2.jpg" width="640" /></a></p><p>Leela had some initiative, its rooks controlled open files in the center. Leela attacked the exposed white king with a rook and queen, it also captured pawns on the queen side. Stockfish sent a rook and queen to attack the black king, it gave a rook for a bishop but then Leela had to give a rook to avoid mate. Both engines pushed passers forward, Stockfish queened first and mated. There were two white wins in this game pair, Stockfish leads 21-15.</p><p>Games 75-76 started with a 24-ply sideline in the Sicilian accelerated Dragon, Modern variation. White pushed pawns on the king side and its king was uncastled in the center, black had an eval advantage. In game 75 the engines played out a long PV agreement, pawn exchanges opened the center and king side, most pieces were exchanged and the game reached a RBN vs RBN position. Stockfish had a passer in the center, evals came down as Leela blocked the passer and kept its pieces safe. Leela gave a rook for a bishop, all pawns were captured and the game was adjudicated. Game 76 repeated game 75 for 39 plys, reaching the same RBN vs RBN position. Stockfish kept its pawns safe and blocked the black passer. The engines reduced to a rook ending, evals came down and the game was adjudicated.</p><p>Games 77-78 started with a 22-ply line in the Ruy Lopez, Arkhangelsk variation, played in high level human chess. All pieces and pawns were on the board and the black king was in the center uncastled. In <a href="https://tcec-chess.com/#div=sf&game=77&season=25">game 77</a> Stockfish castled long and tried to attack the king side but was not strong enough. Leela's eval started to increase, it opened a file in the center and exchanged minor pieces. In a long PV agreement Stockfish's eval came down and then jumped up, Stockfish created a passer in the center while Leela captured a pawn and created an advanced passer on the king side. After another pawn trade Leela cleared all the black pawns on the king side and added 2 more connected passers.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgOJtGRgClhz-QOOPhISwBsNwNxUm_BKOvrwkh1xY88CDyPgnMsiqpiXwSF_9ci1Be1CcAulaLZxhBgDcgFrluEU6fD0jzI23LIjjwmn3fYs0Ht7lhFGX6uh6D0ajhmIh7GIve20JHLaWG_xv11WQP6BXD1Zq-if_gCqrIsyujgKoSfmh7Pcq4qOIi3YqQ/s1161/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="696" data-original-width="1161" height="384" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgOJtGRgClhz-QOOPhISwBsNwNxUm_BKOvrwkh1xY88CDyPgnMsiqpiXwSF_9ci1Be1CcAulaLZxhBgDcgFrluEU6fD0jzI23LIjjwmn3fYs0Ht7lhFGX6uh6D0ajhmIh7GIve20JHLaWG_xv11WQP6BXD1Zq-if_gCqrIsyujgKoSfmh7Pcq4qOIi3YqQ/w640-h384/pic1.jpg" width="640" /></a></div><p>In another long PV agreement each engine blocked an advancing passer and eventually captured it. The minor pieces were traded, on move 50 the queens were exchanged and the game reached a double rook ending with white a pawn up and two passers on the king side.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi4YLtg26lAHbzmXtRMjCxV-YtuLIDas35tS9XA2dXWLROm6W3He9ldjUmGQ_DnhFCoJ67Ulu61mML5_0CZun38PbZzCQm3sfZ4RFJBvmw5lubZh13nptf9E1Su9DyuXdNrAmpXbaetaCY0dF38NdKSUEZKJlDM5CTtApgjVAQfXyzPSE_M53JHeLRSZCs/s1165/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="694" data-original-width="1165" height="382" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi4YLtg26lAHbzmXtRMjCxV-YtuLIDas35tS9XA2dXWLROm6W3He9ldjUmGQ_DnhFCoJ67Ulu61mML5_0CZun38PbZzCQm3sfZ4RFJBvmw5lubZh13nptf9E1Su9DyuXdNrAmpXbaetaCY0dF38NdKSUEZKJlDM5CTtApgjVAQfXyzPSE_M53JHeLRSZCs/w640-h382/pic2.jpg" width="640" /></a></p><p>Leela pushed the passers slowly forward, Stockfish captured one while Leela captured a pawn on the queen side. Stockfish blocked the passer on the 6th rank and Leela captured another pawn and created a passer on the queen side. Leela pushed both passers to the 7th rank, Stockfish couldn't stop a queening and the game ended in a tablebase win.</p><p>In <a href="https://tcec-chess.com/#div=sf&game=78&season=25">game 78</a> Leela was more active in its king side attack, it moved its queen to h3 and forced Stockfish to weaken the pawn support for its king. Stockfish ignored the attack, it opened the a file and moved its queen to the queen side. Leela gave a pawn, chose not to take the knight Stockfish offered and added a second rook to the attack.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi4a1ppC3GAec7B6ukS5f-RUxCfZOYZjCPJ2VLJMT9p5_w-NHsf81rqBkyI7a63RB4HGTEFGwYGUzak13NEfz_vxPg-BEI-zm79X2Akd2bq282eR_zI-iE8RoNYZUwqDqYl71cGYRlIbj0dzIFaHciuHju9KPB79XMfh7LLbxm56Htx9V-NcwEIM0bxusw/s1192/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="691" data-original-width="1192" height="372" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi4a1ppC3GAec7B6ukS5f-RUxCfZOYZjCPJ2VLJMT9p5_w-NHsf81rqBkyI7a63RB4HGTEFGwYGUzak13NEfz_vxPg-BEI-zm79X2Akd2bq282eR_zI-iE8RoNYZUwqDqYl71cGYRlIbj0dzIFaHciuHju9KPB79XMfh7LLbxm56Htx9V-NcwEIM0bxusw/w640-h372/pic1.jpg" width="640" /></a></div><p>Stockfish moved the queen to the king side, Leela captured the h pawn but that was the end of its attack. Leela's queen side seemed solid, yet evals continued to increase. Stockfish exchanged queens and a pair of bishops, then after a while it traded a rook for a knight and captured a pawn. The game reached a RNN vs RRB position.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjgATi1hKfvo9eF0izyImJbf-eMAXhSl1pJjUAZ-y54TXgQF4n2W_6BSuhm0ZB_rqBW8vMKmPjq-nPSWLAzjCVJOrOA-A7KhqzakS3gxjvoyWMIxU-VD8AdC4GrSsRhkC4u4sDQ8bdZO5xCe9iZZV4SOeQ3HLUABGZ2XSpu7cerb4T9i4k9AjRAWnVYcYs/s1176/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="694" data-original-width="1176" height="378" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjgATi1hKfvo9eF0izyImJbf-eMAXhSl1pJjUAZ-y54TXgQF4n2W_6BSuhm0ZB_rqBW8vMKmPjq-nPSWLAzjCVJOrOA-A7KhqzakS3gxjvoyWMIxU-VD8AdC4GrSsRhkC4u4sDQ8bdZO5xCe9iZZV4SOeQ3HLUABGZ2XSpu7cerb4T9i4k9AjRAWnVYcYs/w640-h378/pic2.jpg" width="640" /></a></p><p>Leela had a material advantage, but the white knights were very strong together and covered many squares. Stockfish exchanged pawns and created a passer in the center. Leela captured two pawns but lost the bishop, it gave a rook for a knight but couldn't stop the white passer queening, mate followed a few moves later. There were two white wins in this game pair, Stockfish leads 22-16.</p><p>Games 79-80 started with a rare sideline in the Queen's Indian defense, Kasparov-Petrosian variation. In <a href="https://tcec-chess.com/#div=sf&game=79&season=25">game 79</a> the engines opened files with pawn exchanges in the center and queen side. Leela went a pawn up and exchanged queens, then it captured another pawn. In a series of exchanges Leela traded a rook for two minor pieces and the game reached a RB vs BBN position on move 30.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhyTxPhSDN3njmYR6T3wH7hHtHQzkv1XuXkshDPQzCp-LgOa6ZVviv1X4Huw2t7VVI1d8zBpKSkiWKhW_WDpkGctZ8xwdcDVEnCDI7tJ1_8I9PjnkKXNfqtv4l2txS7H5uy34L18a_NlQ9W4qlrEojBfu13MJfbt_4sAtn3wPlHEeWovZoEot76gBPmrf4/s1168/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="694" data-original-width="1168" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhyTxPhSDN3njmYR6T3wH7hHtHQzkv1XuXkshDPQzCp-LgOa6ZVviv1X4Huw2t7VVI1d8zBpKSkiWKhW_WDpkGctZ8xwdcDVEnCDI7tJ1_8I9PjnkKXNfqtv4l2txS7H5uy34L18a_NlQ9W4qlrEojBfu13MJfbt_4sAtn3wPlHEeWovZoEot76gBPmrf4/w640-h380/pic1.jpg" width="640" /></a></div><p>Leela pushed its two passers forward, Stockfish captured one but lost a bishop. Stockfish blocked the other passer with the knight, Leela had a very hard time trying to improve its position. On move 56 Leela captured a pawn, on move 73 it gave a pawn and then the black knight moved. Leela captured a pawn, only on move 88 it managed to push its passer forward. Stockfish saw a quicker win, but eventually it started to lose material and the game ended in a tablebase win on move 105.</p><p>In <a href="https://tcec-chess.com/#div=sf&game=80&season=25">game 80</a> Stockfish pushed the h pawn forward and it was exchanged on h6, Leela castled short despite this and Stockfish kept its king in the center. Leela pushed pawns and opened the queen side, the engines exchanged minor pieces in the center. Stockfish's eval started to increase while Leela's eval was stable and even decreased a little.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhSQcTXR6IHoFRg1x3sq_81cyjpwHQ1emid72O4Dm1dc2JeXw1Xx9afPquZkAcW6BHhu1AoGb6VErWz80aLLnmnpfas78T_rvbS6ChTXq91U_F9lP477xcLviQop72AwHxTbdPJv9QE5w04LMedvdssX18q9MuRXQ2CfbeJCLWD8dQ_WhhX6BcVSHrKYkc/s1180/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="691" data-original-width="1180" height="374" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhSQcTXR6IHoFRg1x3sq_81cyjpwHQ1emid72O4Dm1dc2JeXw1Xx9afPquZkAcW6BHhu1AoGb6VErWz80aLLnmnpfas78T_rvbS6ChTXq91U_F9lP477xcLviQop72AwHxTbdPJv9QE5w04LMedvdssX18q9MuRXQ2CfbeJCLWD8dQ_WhhX6BcVSHrKYkc/w640-h374/pic1.jpg" width="640" /></a></div><p>The engines seemed to shuffle for a while, though Stockfish's eval steadily increased. After move 38 Leela's eval reacted as well. Stockfish blocked the center with its major pieces, on move 51 it exchanged a pair of rooks and reduced to a QRB vs QRB position.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjBhyjnjKDT5u9FJ6f3wvPAUYrga8ZIRf_xowOAPwTDO6M_r4ph41wot1SEDDnUiBHpSbGk1rz6uEd4Yuyz6BuCMu9xsmCx_fUNqzX0KxcF-UFt0p7v5z_GBMxfBVY1K0129V-AHdyPRqmsj1jeMvPIwSSzQL_b_OmCtKqSt1iFWMAqna8j9XZYjOhhOUE/s1177/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="691" data-original-width="1177" height="376" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjBhyjnjKDT5u9FJ6f3wvPAUYrga8ZIRf_xowOAPwTDO6M_r4ph41wot1SEDDnUiBHpSbGk1rz6uEd4Yuyz6BuCMu9xsmCx_fUNqzX0KxcF-UFt0p7v5z_GBMxfBVY1K0129V-AHdyPRqmsj1jeMvPIwSSzQL_b_OmCtKqSt1iFWMAqna8j9XZYjOhhOUE/w640-h376/pic2.jpg" width="640" /></a></p><p>Stockfish exchanged its b pawn and moved its queen to the back rank. It captured the black d pawn and exchanged bishops, seeing the win far in its PV. After exchanging queens the white king moved forward on the king side. Stockfish was only one pawn up, but after exchanging a pair of pawns it had a pawn majority in the center. Leela had a passer but the white king blocked it long enough until it captured the black e pawn. The white passers were faster and the black king was trapped, the game ended in a tablebase win before mate. There were two white wins in this game pair, Stockfish leads 23-17.</p><p><br /></p>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com0tag:blogger.com,1999:blog-4430065842059358622.post-3372751604129791702023-10-26T20:12:00.003+03:002023-10-26T20:12:53.737+03:00Season 25 superfinal games 61-70<p>After 70 games Stockfish leads 20-13 with 37 draws. Stockfish's lead is 7 wins after each engine won a game pair. There were 3 drawn game pairs, two had two white wins. Leela game pair win came after 17 game pairs which were either drawn or Stockfish wins. Leela almost won a second game pair, but an inaccuracy late in game 70 gave Stockfish the win and the game pair was drawn.</p><p>Games 61-62 started with a sideline of the QGD, Semi Slav defense, with the black king uncastled and the black queen on h6. In <a href="https://tcec-chess.com/#div=sf&game=61&season=25">game 61</a> evals increased quickly after the start, Stockfish kept its king in the center and Leela forced it to move. Leela moved a knight forward and traded it for a rook.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhMlXfhOO4xeOFeEyWTLGfZXBfJb32xAMtRycSsL-rKvNNIMspY7xz7gCPIH6P1WmkQJshWFcHyFEDBY0vpA87OjGc0_gDVk1tEqfCEwAhOZr0nd_HMFLs0m23LFEW6xpXjW9xqcLiNhBMLbM_O5k4VnGPd-sA6eVGmtYtuvwPc0_t0TGEhkTBMCRACK9k/s1159/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="691" data-original-width="1159" height="382" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhMlXfhOO4xeOFeEyWTLGfZXBfJb32xAMtRycSsL-rKvNNIMspY7xz7gCPIH6P1WmkQJshWFcHyFEDBY0vpA87OjGc0_gDVk1tEqfCEwAhOZr0nd_HMFLs0m23LFEW6xpXjW9xqcLiNhBMLbM_O5k4VnGPd-sA6eVGmtYtuvwPc0_t0TGEhkTBMCRACK9k/w640-h382/pic1.jpg" width="640" /></a></div><p>Leela pushed pawns on the queen side, after some shuffling Leela captured a pawn on the king side and created a passer. The white queen moved forward on the queen side and captured two pawns, creating a passer there as well. Leela gave a pawn and add two more connected passers on the queen side.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg0a2wCHPKzvCOUUFYiNorZviSbXX7lhZBV2Oy-v8V0BuLV76yT8OFvaglIBNS8tUi8ZFifSkR38oxa3OM8ro6dz2zrCQ3FCSMTaFReY9BVevDPGuHLo5baNKs8TFgnPIbowKNyGG9ko7aN8k0vd2cWbRcq46Qnx7Xkg8gsPADoG-lrdEgxYb2_v6rakGg/s1171/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="693" data-original-width="1171" height="378" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg0a2wCHPKzvCOUUFYiNorZviSbXX7lhZBV2Oy-v8V0BuLV76yT8OFvaglIBNS8tUi8ZFifSkR38oxa3OM8ro6dz2zrCQ3FCSMTaFReY9BVevDPGuHLo5baNKs8TFgnPIbowKNyGG9ko7aN8k0vd2cWbRcq46Qnx7Xkg8gsPADoG-lrdEgxYb2_v6rakGg/w640-h378/pic2.jpg" width="640" /></a></p><p>Stockfish lost a bishop for two of the passers, Leela gained more material and mated.</p><p>In <a href="https://tcec-chess.com/#div=sf&game=62&season=25">game 62</a> Stockfish pushed pawns in the center, it traded a rook and a pawn for two minor pieces. The black queen captured a knight and walked into a trap, Stockfish captured the queen for a rook. The game reached a QBN vs RRB position on move 25.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgjntx7XVKgt09ISkj9HQgmQYURzpHBfyq5OKWpZSft07IEvgnukmjW8VnrteP87s_e8Tb1CLrOnJL-mHc0EelAo-o0X8SF5sEvemF99knNxccbHrJG8_YEC1JS063M1SaIWXco0ebVjDvaCZlDPT3NIiNQYZBt2kskH0EPT6-ODqEMXvIuyuyq3cvSxBs/s1173/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="691" data-original-width="1173" height="378" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgjntx7XVKgt09ISkj9HQgmQYURzpHBfyq5OKWpZSft07IEvgnukmjW8VnrteP87s_e8Tb1CLrOnJL-mHc0EelAo-o0X8SF5sEvemF99knNxccbHrJG8_YEC1JS063M1SaIWXco0ebVjDvaCZlDPT3NIiNQYZBt2kskH0EPT6-ODqEMXvIuyuyq3cvSxBs/w640-h378/pic1.jpg" width="640" /></a></div><p>Leela was two pawns up, it doubled rooks on the open e file and its eval drifted down. Stockfish's eval steadily increased, it pushed pawns on the queen side and on move 41 exchanged a pair of pawns. Leela's eval started to increase as well, by move 56 the white queen captured two pawns and opened the queen side.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgl6u5G8vP2aZ3Wsz7zk6uJh0jVh2CJmbEeRWA3O1kql5DlEx0tEuFZOMxkauef2oyUYjSHyuTrrQLwGDN5MB3-tpUCwPyXyfg0ly-_phWxOy74eZhAvVmYhxuKHY5Fu09bBb_I0VmWQfCHN7cft2Y5ZeXR-oD5CvzmpOKnDYAfNENpgb1o0TsezUObZGs/s1162/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="694" data-original-width="1162" height="382" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgl6u5G8vP2aZ3Wsz7zk6uJh0jVh2CJmbEeRWA3O1kql5DlEx0tEuFZOMxkauef2oyUYjSHyuTrrQLwGDN5MB3-tpUCwPyXyfg0ly-_phWxOy74eZhAvVmYhxuKHY5Fu09bBb_I0VmWQfCHN7cft2Y5ZeXR-oD5CvzmpOKnDYAfNENpgb1o0TsezUObZGs/w640-h382/pic2.jpg" width="640" /></a></p><p>Leela pushed its passer to the 2nd rank, Stockfish traded its queen for the two black rooks and stopped the passer. The game ended in a tablebase win. There were two white wins in this game pair, Stockfish leads 18-11.</p><p>Games 63-64 started with a 20-ply sideline in the QGD, Albin counter-gambit, white was a pawn up and black had a passer in the center. In game 63 there was a long PV agreement after the start, the engines exchanged minor pieces and Leela captured the black passer. Evals came down, after exchanging queens the game reached a RRB vs RRB position. Stockfish slowly captured the pawns back, the engines reduced to a rook ending. Leela had a passer but it couldn't push it beyond the 6th rank. The game was adjudicated when Leela lowered its eval for the draw rule. </p><p>In <a href="https://tcec-chess.com/#div=sf&game=64&season=25">game 64</a> Stockfish pushed pawns on the queen side and captured the black passer. On move 20 Leela played h6, this weakened the black king and Stockfish's eval jumped. Stockfish attacked the king side with its queen and a knight, Leela gave a rook for the knight, Stockfish sacrificed another knight to expose the black king. Leela was forced to trade its queen for a rook to save its king from mate. On move 29 there was an imbalance of Q vs BBN on the board with high evals.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgUSiNrlQe0-YErTMNrnvMLFnYAxtxOQKrxPX16z_kdI1sm9JxRvQzn7GnPxhO6kdoKE_tcUHb4EnsvLxyjB7VKV-7Wd5L4KyE5QqdJQ0YypNGuX4T2uK89s-fXukq06fLNnVnRNZmzX_Oc3sqIPjBOsang2yzpj76IXwnWONyrer_-JIPgiTVJMeOtDuA/s1183/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="694" data-original-width="1183" height="376" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgUSiNrlQe0-YErTMNrnvMLFnYAxtxOQKrxPX16z_kdI1sm9JxRvQzn7GnPxhO6kdoKE_tcUHb4EnsvLxyjB7VKV-7Wd5L4KyE5QqdJQ0YypNGuX4T2uK89s-fXukq06fLNnVnRNZmzX_Oc3sqIPjBOsang2yzpj76IXwnWONyrer_-JIPgiTVJMeOtDuA/w640-h376/pic1.jpg" width="640" /></a></div><p>Stockfish ignored the black passer and continued to attack with its queen and rook. After exchanging rooks Stockfish captured the black passer. Stockfish pushed a passer on the king side, Leela lost a bishop for it. The white king moved forward and Stockfish mated. Stockfish wins the game pair, it leads 19-11.</p><p>Games 65-66 started with a 22-ply sideline in the Sicilian Taimanov, Szen variation, that appeared in a Fischer-Taimanov game. Both kings were uncastled, black had a strong knight on d4 as well as an eval advantage. In game 65 Stockfish grabbed the g pawn with a rook, this gave Leela time to improve its piece arrangement. Leela drove the black knight on d4 away, both kings moved forward and evals came down. The engines exchanged all rooks through the open g file and reduced to a QB vs QN position, evals were low and the game was adjudicated early on move 36.</p><p>In <a href="https://tcec-chess.com/#div=sf&game=66&season=25">game 66</a> Leela also grabbed the g pawn as in game 65. The pieces stayed on the board longer, Stockfish moved a knight to d5, it drove the black knight from d4 and Leela moved it to c5. Stockfish castled long and (negative) evals started to increase. Leela managed to exchange the knights in the center, after queens were exchanged the game reached a RBN vs RBB position on move 40.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi779aWaaxcok20Kwue4kWKqIU_xmkTure42sbRdHh9DFqf-uYr5_6WEXd9b5JC4tyZGeZoxkuo_wzrLzZ0ha1egaE_ScW8lEwp_0uAsaBpNHSQ49-jOaDhxoiUq7ATMgxQBQ49hADkVS9fxPDZkdOZ9pMlEYTEOoVsYtDhFJi3OVoxe0cIvgI6kDXfFhQ/s1171/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="697" data-original-width="1171" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi779aWaaxcok20Kwue4kWKqIU_xmkTure42sbRdHh9DFqf-uYr5_6WEXd9b5JC4tyZGeZoxkuo_wzrLzZ0ha1egaE_ScW8lEwp_0uAsaBpNHSQ49-jOaDhxoiUq7ATMgxQBQ49hADkVS9fxPDZkdOZ9pMlEYTEOoVsYtDhFJi3OVoxe0cIvgI6kDXfFhQ/w640-h380/pic1.jpg" width="640" /></a></div><p>The engines blocked the queen side, Stockfish walked its king to the king side and pushed the h pawn forward. Leela exchanged pawns and got rid of the white e pawn, suddenly it was 3 pawns against 1 on the king side. Leela hid its king behind the white passer and shifted the rook to the queen side. The black rook moved to the 2nd rank and trapped the white king.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgHsb8Lx0j9S2kgbMCNtannNFyd5CvhNc9ZC94ORyYRPySiVlp2fR0DPdO-G7vpTPCsUubLsd_NW5QxLvtREUuxIl66pjFQdaQ6xtU6LIhHBLR95ph0dv68-kWuz5z08CM3ROSvuDWKNQPbK8Yk49YDFO3Foe0syGL0jBypeVoZhzTFw3wPOgYijf5NNp8/s1180/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="697" data-original-width="1180" height="378" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgHsb8Lx0j9S2kgbMCNtannNFyd5CvhNc9ZC94ORyYRPySiVlp2fR0DPdO-G7vpTPCsUubLsd_NW5QxLvtREUuxIl66pjFQdaQ6xtU6LIhHBLR95ph0dv68-kWuz5z08CM3ROSvuDWKNQPbK8Yk49YDFO3Foe0syGL0jBypeVoZhzTFw3wPOgYijf5NNp8/w640-h378/pic2.jpg" width="640" /></a></p><p>Leela captured the white h pawn, then gave a pawn to get the white f pawn out of the way. Leela pushed pawns on the king side and Stockfish lost pieces trying to avoid mate. Stockfish raced to queen a passer but was mated on the other side. Leela wins the game pair, Stockfish leads 19-12.</p><p>Games 67-68 started with a rare sideline of the KID, four pawns attack. In game 67 the engines opened the d file, a black knight made an unusual journey of 5 moves and was traded for a bishop. In a series of exchanges the engines reduced to a RRB vs RRB position and evals came down. Leela doubled rooks on the d file, after a few pawn exchanges the engines started to shuffle. After 40 moves Leela exchanged a pair of rooks and the game was adjudicated. In game 68 the engines opened the d file and also the b file, Stockfish moved its king forward without castling. The white queen moved forward, in a long PV agreement there were many exchanges and Stockfish gave a rook for a bishop. For a few moves Stockfish's eval jumped, then unexpectedly dropped back even though it anticipated Leela's move. Stockfish regained a rook for a bishop, after exchanging queens the game reached a rook ending. Stockfish was up a pawn with a passer, Leela gave a pawn and as a result all the white pawns were isolated and a pair was doubled. Leela held the draw, though it wouldn't lower its eval for a long time</p><p>Games 69-70 started with a rare sideline of the Pirc defense, Austrian attack. In <a href="https://tcec-chess.com/#div=sf&game=69&season=25">game 69</a> Leela attacked the king side, the engines exchanged minor pieces and Stockfish was a pawn up but the black king was vulnerable. After a few pawn moves and some shuffling Stockfish moved its queen to a3, perhaps to attack the unguarded b3 pawn.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgboumOL8w8M1NV7gZJ94zLvh_P41RDyB8zmRNXxq37rvUeHSPlYXwYz6HI84-5gnVEmxy1ts_sRJAvdoe79FplNoj9bsnaQkO5r8TQcdbhB6e3iQ_Bvc4rZRBzw7EAWvKtZPSLlZuC8PY6I34U5J6g-2c4yt947K08975_6BKYl6Nt0-GF5BtvK1dOchY/s1170/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="691" data-original-width="1170" height="378" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgboumOL8w8M1NV7gZJ94zLvh_P41RDyB8zmRNXxq37rvUeHSPlYXwYz6HI84-5gnVEmxy1ts_sRJAvdoe79FplNoj9bsnaQkO5r8TQcdbhB6e3iQ_Bvc4rZRBzw7EAWvKtZPSLlZuC8PY6I34U5J6g-2c4yt947K08975_6BKYl6Nt0-GF5BtvK1dOchY/w640-h378/pic1.jpg" width="640" /></a></div><p>Leela thought this was a mistake and its eval jumped, Stockfish's eval reacted only 3 moves later. Leela attacked the black king and Stockfish quickly moved its queen back to help. Leela regained the pawn, after exchanging queens it created a passer on the queen side. Then it captured two more pawns and reduced to a RN vs RB position.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEggrv2LvxgBDNDZQLjmom61tzTN5XrJjdH9JE0hMPx6TUdzhql7Nlgvlph1wP70eQI-zDMGlRub0voNO2cYH0cuAtrq-lh_bhzCW5m4zvI7TQ80S8rnn9ewZ26O89ks3NCZA5HoSODztULfjvf65vq2VcMqXODZ44cxg9WCE06NMLc4dcwSobkZh0-0Z-Q/s1159/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="691" data-original-width="1159" height="382" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEggrv2LvxgBDNDZQLjmom61tzTN5XrJjdH9JE0hMPx6TUdzhql7Nlgvlph1wP70eQI-zDMGlRub0voNO2cYH0cuAtrq-lh_bhzCW5m4zvI7TQ80S8rnn9ewZ26O89ks3NCZA5HoSODztULfjvf65vq2VcMqXODZ44cxg9WCE06NMLc4dcwSobkZh0-0Z-Q/w640-h382/pic2.jpg" width="640" /></a></p><p>While Stockfish focused on the white a passer Leela managed to capture the last black pawn and create passers on the king side. Leela pushed passers forward, Stockfish stopped one before the game ended in a tablebase win.</p><p>In <a href="https://tcec-chess.com/#div=sf&game=70&season=25">game 70</a> there were early exchanges, the engines opened the f file and exchanged a pair of rooks. The game reached a QRB vs QRN position on move 20, there were a few pawn moves and the engines started to shuffle. On move 74 the engines opened the a file and shuffling resumed, evals drifted down and the game seemed to be heading for a draw.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgMGYoOtPKGb6Oq-T7S3w7Xi8bRrFkRnNOKcqwSc2LzFPLQpAHsoBn9SgtjLdG8TQmVlkxCw0iQr8xreld6h_HRtnWNJz698sMKPVFyU_npJYfxa4nB6Fyq38A7xiIsyEsiWbbkRjgiva9mVN681Rc90BZoc-IJncwJC24cUNpmBeq7iKLn5spoURLHGeU/s1176/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="697" data-original-width="1176" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgMGYoOtPKGb6Oq-T7S3w7Xi8bRrFkRnNOKcqwSc2LzFPLQpAHsoBn9SgtjLdG8TQmVlkxCw0iQr8xreld6h_HRtnWNJz698sMKPVFyU_npJYfxa4nB6Fyq38A7xiIsyEsiWbbkRjgiva9mVN681Rc90BZoc-IJncwJC24cUNpmBeq7iKLn5spoURLHGeU/w640-h380/pic1.jpg" width="640" /></a></div><p>Stockfish thought Leela's move 89 was an inaccuracy and its eval started to increase, Leela's eval increased as well. Both engines were low on time and played in blitz mode. Stockfish managed to double rook and queen on the a file, then moved its rook forward and exchanged rooks. The white queen moved forward and used a mate threat to capture a pawn and create a passer. Stockfish blocked Leela's attempt to counter attack, then it captured a second pawn.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgo1mj2jiXWnvCFCApVJ03MaDOXWG0zLb4lyGek_ihxnQZ0JTjgRNxTWzBDpLy5NSIgqf_7DZGNmtltBkS0RAMOyWPd1GpQrU5nKyLk3p4wBEXyPqEadsSxJpTrvGkusMqrLEXYcv5FzJaIijoBJeQhvZFTlog8Cpe9NH8CMSVdlgnWwCUm_lZvLERAhjs/s1171/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="694" data-original-width="1171" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgo1mj2jiXWnvCFCApVJ03MaDOXWG0zLb4lyGek_ihxnQZ0JTjgRNxTWzBDpLy5NSIgqf_7DZGNmtltBkS0RAMOyWPd1GpQrU5nKyLk3p4wBEXyPqEadsSxJpTrvGkusMqrLEXYcv5FzJaIijoBJeQhvZFTlog8Cpe9NH8CMSVdlgnWwCUm_lZvLERAhjs/w640-h380/pic2.jpg" width="640" /></a></p><p>Stockfish exchanged queens, Leela managed to regain the two pawns including the passer on the queen side. However, the black king was too far to defend the isolated pawns on the king side, Stockfish captured two pawns, queened and mated. There were two white wins in this game pair, Stockfish leads 20-13.</p><p><br /></p>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com0tag:blogger.com,1999:blog-4430065842059358622.post-84443519168612436442023-10-24T23:49:00.001+03:002023-11-03T00:44:17.984+02:00Season 25 superfinal games 51-60<p>After 60 games Stockfish leads 17-10 with 33 draws. Stockfish extended its lead to 7 wins after another game pair win. There were two game pairs with two white wins. After 30 game pairs Leela still has only one game pair win. Stockfish won 5 of the last 15 game pairs.</p><p>Games 51-52 started with a rare 20-ply sideline in the KID Fianchetto, classical main line. In game 51 there was one pair of pawns exchanged after the start, the engines played behind their pawn lines for a long time. The first piece exchange was on move 32, afterwards there were a few pawns and minor pieces exchanged. On move 45 Stockfish's eval dropped, it gave a rook for a bishop and three pawns, then reduced to a QR vs QN position. Leela managed to capture 3 pawns back, its eval slowly came down and the game was adjudicated.</p><p>In <a href="https://tcec-chess.com/#div=sf&game=52&season=25">game 52</a> Leela locked the center early, there was one pawn exchange on the queen side and the engines started to shuffle. Stockfish extended the shuffle beyond move 80 with pawn moves. Evals slowly started to increase, on move 88 Leela pushed the f pawn.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEitC831Oc7IJ5N5o7RjTedgnKxrWK8ydJhD0UarM8fPKxTQBPNWcQCLvU6Zp7P1DOY9ZjhpQHNgniVcpkantRKW5nCtbGl1nG28wafNmeoAJMJjSnjHQmQBjJ7WtlnGqqffQ0OmBQ68nXYjpWUptVU8TOCEeoJgwVmOTYkd2yOb997BK2MHIGRt8_sn13g/s1171/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="690" data-original-width="1171" height="378" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEitC831Oc7IJ5N5o7RjTedgnKxrWK8ydJhD0UarM8fPKxTQBPNWcQCLvU6Zp7P1DOY9ZjhpQHNgniVcpkantRKW5nCtbGl1nG28wafNmeoAJMJjSnjHQmQBjJ7WtlnGqqffQ0OmBQ68nXYjpWUptVU8TOCEeoJgwVmOTYkd2yOb997BK2MHIGRt8_sn13g/w640-h378/pic1.jpg" width="640" /></a></div><p>Both engines were low on time and played quickly. After a few moves Stockfish opened the king side, evals increased rapidly as the engines exchanged pieces and pawns. On move 106 the game reached a R vs NN imbalance with white two pawns up.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhXpe3oxp6Mziu8fVxGPbtCMggUxbixEG2bYvAD1YzIMBVLs_dC5SYoRszpg7psI2kdpNH__cADEeByeAVaAhVUAiI63eXU8RSvK_XwqPL9dm-hStiYzSkeidorMrITqMsYPqgxJfs3rV69IdQFHQiFl6eATG2CEPIfRI-njhbyIFyy6JxazAYSX3sXW9g/s1176/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="693" data-original-width="1176" height="378" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhXpe3oxp6Mziu8fVxGPbtCMggUxbixEG2bYvAD1YzIMBVLs_dC5SYoRszpg7psI2kdpNH__cADEeByeAVaAhVUAiI63eXU8RSvK_XwqPL9dm-hStiYzSkeidorMrITqMsYPqgxJfs3rV69IdQFHQiFl6eATG2CEPIfRI-njhbyIFyy6JxazAYSX3sXW9g/w640-h378/pic2.jpg" width="640" /></a></p><p>Stockfish captured another pawn and it had 3 passers on the queen side. Leela lost material quickly, Stockfish queened and mated. Stockfish wins the game pair, it leads 15-8.</p><p>Games 53-54 started with a rare sideline in the KID Saemisch, Yates defense, played in high level human chess. In game 53 the engines blocked the center and Leela castled long. Stockfish gave a pawn on the king side, giving Leela a passer and hiding its king behind it. Leela gave a knight for two pawns to open the king side and evals dropped. In a series of exchanges the engines reduced to a RR vs RBN position, white two pawns up. Leela still had 7 pawns, its rooks were not effective and the engines shuffled. Leela gave two pawns and captured a knight, evals were low enough and the game was adjudicated. In game 54 Stockfish opened the d file and captured a pawn, queens were off early and evals came down slowly. The engines shuffled for a long time, Stockfish moved a pawn to reset the 50-move draw counter, Leela pushed a passer to the 2nd rank. Stockfish captured another pawn and gave a rook for a knight, the game reached a BN vs RN position with low evals and was adjudicated.</p><p>Games 55-56 started with a rare sideline in the Nimzo-Indian defense, three knights variation. In game 55 a series of exchanges opened the center. Stockfish kept its king uncastled and Leela forced it to move, blocking the king side rook. Evals came down after most minor pieces were exchanged, on move 29 the game reached a QRR vs QRR position. Stockfish freed its trapped rook, Leela traded its two rooks for the black queen. The engines traded pawns, Leela was a pawn up but Stockfish held the draw. The game was adjudicated when Leela lowered its eval for the draw rule. Game 56 started similarly with small variations, again the black king side rook was trapped. Leela developed the rook through the h file. There was a lot of shuffling and some pawn and piece exchanges, evals came down. On move 53 the engines reduced to a Q vs RR position. Stockfish was two pawns up but not enough to win, the game was adjudicated when Stockfish lowered its eval for the draw rule.</p><p>Games 57-58 started with a rare 22-ply sideline in the Ruy Lopez closed variation. In <a href="https://tcec-chess.com/#div=sf&game=57&season=25">game 57</a> the center was blocked and there were no exchanges after the start. Evals slowly increased, Leela pushed pawns on the king side, after move 28 there were a few pawns and minor pieces exchanged and Leela placed a pawn on h6. </p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhdlIqn1CdHJVlvmMPOuPXYMasQEPxiyEsgE1Y2Jir0SVdbi9xfWdm6UkKgwtLkDQQAhwd3AKdiNjkaLshErQVkqtXYRpWyCIbHwuZHIe4bMtNOQQDeN-9-9GAw9T3wXiyA8ZRtIcpVE6eSg55mntd0udxexShWWPYXbhqGfzyXYYhlmUqu5he4FdKUvmg/s1165/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="694" data-original-width="1165" height="382" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhdlIqn1CdHJVlvmMPOuPXYMasQEPxiyEsgE1Y2Jir0SVdbi9xfWdm6UkKgwtLkDQQAhwd3AKdiNjkaLshErQVkqtXYRpWyCIbHwuZHIe4bMtNOQQDeN-9-9GAw9T3wXiyA8ZRtIcpVE6eSg55mntd0udxexShWWPYXbhqGfzyXYYhlmUqu5he4FdKUvmg/w640-h382/pic1.jpg" width="640" /></a></div><p>Queens were exchanged, more pawn exchanges opened the board. On move 50 Stockfish gave a rook for a bishop and the white h pawn, the game reached a RRN vs RBN position. Stockfish was a pawn up with connected passers on the king side, but Leela had a significant eval advantage.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjw40bWVp2W-1wZQ8PFxKmjzk5of_Bli2IdlzX7v1mzykSG9A6SVDjfmFj4bgttjdqiG89yLTQtCAazABUvI8e_5Kw-AHgm7HWkzFGEUF-z_zcdVPgmTTl4XJodzL7-BKCcWiY2zPBGEmUJvPDd7HVnSQJnLIcDXSBr3a9rvERelmb90Oa3yKWsKpKqdtw/s1168/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="691" data-original-width="1168" height="378" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjw40bWVp2W-1wZQ8PFxKmjzk5of_Bli2IdlzX7v1mzykSG9A6SVDjfmFj4bgttjdqiG89yLTQtCAazABUvI8e_5Kw-AHgm7HWkzFGEUF-z_zcdVPgmTTl4XJodzL7-BKCcWiY2zPBGEmUJvPDd7HVnSQJnLIcDXSBr3a9rvERelmb90Oa3yKWsKpKqdtw/w640-h378/pic2.jpg" width="640" /></a></p><p>The black passers were too far behind to be a threat. Leela captured the a pawn and pushed two passers forward. Stockfish lost material trying to prevent a queening, Leela queened a pawn in the end and the game was adjudicated before mate.</p><p>In <a href="https://tcec-chess.com/#div=sf&game=58&season=25">game 58</a> again the center was blocked, this time Leela chose to open the b file with the first pawn exchange. Evals were stable, there were no other exchanges and the focus shifted to the king side. After some preparation Stockfish doubled rooks on the f file and on move 39 it pushed the f pawn forward.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjXIhycbX19aIIfoDuWcYTZDSu0FW1WqIvV9G2hkKVbJ1Ja3kY57-iAMcKPwp9KzSIRxYYTmGPXUM1DkXesv_h8E4mcd2xnVbsMEE61a1fMMOTFqlAeR9Zymidri96Y57AnBooQ0a775X5ZPj4GqiNXd-cJimpu7d4z4Jo3h6VhA0ESmHmlZEUuvGe2go0/s1177/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="693" data-original-width="1177" height="376" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjXIhycbX19aIIfoDuWcYTZDSu0FW1WqIvV9G2hkKVbJ1Ja3kY57-iAMcKPwp9KzSIRxYYTmGPXUM1DkXesv_h8E4mcd2xnVbsMEE61a1fMMOTFqlAeR9Zymidri96Y57AnBooQ0a775X5ZPj4GqiNXd-cJimpu7d4z4Jo3h6VhA0ESmHmlZEUuvGe2go0/w640-h376/pic1.jpg" width="640" /></a></div><p>Stockfish expected f6 and opening the f file, Leela chose to take with the g pawn. Stockfish took back with its knight and allowed Leela to take the knight. Stockfish thought these Leela moves were inaccuracies and its eval jumped, Leela's eval also jumped a move too late. The king side opened with the white major pieces attacking the black king. Leela gave a bishop back and exchanged pieces, on move 58 the game reached a QBN vs QR position. </p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh3sZV1rG0-KIX7B6pplN7vPbMTtB5Q1NYxJTjhU2AVuqGUQ0FZBY6ut6TclaNCADdxBrdYTixxWu9b90W_ijMDe3Z6TPfDsU20u5swWzKwyFbviE_UUeUgd_LyHh1ae2bv1Sm5ie-qxRO0P6TvYgppeESomfS5XxnfIQFzRUhBgCsqLroyUtGnMMcH5lU/s1185/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="694" data-original-width="1185" height="374" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh3sZV1rG0-KIX7B6pplN7vPbMTtB5Q1NYxJTjhU2AVuqGUQ0FZBY6ut6TclaNCADdxBrdYTixxWu9b90W_ijMDe3Z6TPfDsU20u5swWzKwyFbviE_UUeUgd_LyHh1ae2bv1Sm5ie-qxRO0P6TvYgppeESomfS5XxnfIQFzRUhBgCsqLroyUtGnMMcH5lU/w640-h374/pic2.jpg" width="640" /></a></p><p>Both kings were exposed but Stockfish found safe squares for its king and slowly moved it forward. Stockfish captured a pawn and exchanged queens, then pushed a passer forward. Leela tried a stalemate trap, Stockfish captured the black rook and promoted the passer to a knight, then mated with minor pieces. There were two white wins in this game pair, Stockfish leads 16-9.</p><p>Games 59-60 started with a sideline of the Ruy Lopez, Bird defense variation. In <a href="https://tcec-chess.com/#div=sf&game=59&season=25">game 59</a> both queens moved forward early, Leela forced the black king to move without castling. There were many early exchanges and the game reached a RB vs RN position with white a pawn up on move 26.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiDFS1W6_1nY_Fir09lus89kz8ymJ8ABU_3hSf0dNB7ipIsEoOO2GEsbcIpRONWddUHmqOQihm8Gg3BJ98nI210gIGu6_vZPEcNp0xfBD4JDZcqtrLVmkgErzHBfuJbBQGnR46-XYWIq6VaXEU7tn_GAJAOIMj5VfREo5iSBwjNgfecgQWF3VKbz198uSw/s1170/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="697" data-original-width="1170" height="382" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiDFS1W6_1nY_Fir09lus89kz8ymJ8ABU_3hSf0dNB7ipIsEoOO2GEsbcIpRONWddUHmqOQihm8Gg3BJ98nI210gIGu6_vZPEcNp0xfBD4JDZcqtrLVmkgErzHBfuJbBQGnR46-XYWIq6VaXEU7tn_GAJAOIMj5VfREo5iSBwjNgfecgQWF3VKbz198uSw/w640-h382/pic1.jpg" width="640" /></a></div><p>Leela thought Stockfish should have taken the rook with its king on move 26, its eval jumped and it offered a rook exchange. Stockfish's eval jumped as well and it refused the offer. Leela had a pawn majority on the king side, after a pawn trade it shifted to a pawn majority on the queen side. The white king slowly moved forward to assist, on move 57 Leela captured another pawn and created connected passers.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhJO5zUWz4RlHuh_UzwHqAyiOT4iimZZEzxdVFjN_vN7Scd3Bk7Cx1S2ROWJBst4fe-6rzGn1PlEmVF0pFYoqoH5alp6IxiwL1gGTgZqpj-68lW3Y7x2SI5CbTYKPDosJimUcwqQaXlGnmwLIcm3JywYMfmYEAgvFQCPoiT3uAvurtQ-30YPNbMYlXqmWI/s1179/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="693" data-original-width="1179" height="376" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhJO5zUWz4RlHuh_UzwHqAyiOT4iimZZEzxdVFjN_vN7Scd3Bk7Cx1S2ROWJBst4fe-6rzGn1PlEmVF0pFYoqoH5alp6IxiwL1gGTgZqpj-68lW3Y7x2SI5CbTYKPDosJimUcwqQaXlGnmwLIcm3JywYMfmYEAgvFQCPoiT3uAvurtQ-30YPNbMYlXqmWI/w640-h376/pic2.jpg" width="640" /></a></p><p>Leela pushed its passers forward, the white king switched to the king side and captured a pawn. Stockfish lost a rook for one passer, Leela queened and mated.</p><p>In <a href="https://tcec-chess.com/#div=sf&game=60&season=25">game 60</a> the white queen moved forward on the king side, Leela castled short despite the threat. Stockfish pushed the f pawn forward and evals increased. The engines exchanged all bishops, Leela stopped the white pawn on f6 and exchanged queens. Only RRN vs RRN were left on move 27.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj8L5u1BTyPyHchcxMdq2QT0FosVffWbTHIy0lPLZmixq4sUSTCt06sZzpD3Mt3xrCEg0L_1qbES7-06SFcwhovS0DuIFwQI9I9mzxFPHv427WH6b4WdIXECfPJKXsH5zz1mz_CQlXRCs0ht1mRqDh6OJ2DlLgJGYkdBlstx3l0ms9byPxsl8j8yRn1PDQ/s1180/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="694" data-original-width="1180" height="376" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj8L5u1BTyPyHchcxMdq2QT0FosVffWbTHIy0lPLZmixq4sUSTCt06sZzpD3Mt3xrCEg0L_1qbES7-06SFcwhovS0DuIFwQI9I9mzxFPHv427WH6b4WdIXECfPJKXsH5zz1mz_CQlXRCs0ht1mRqDh6OJ2DlLgJGYkdBlstx3l0ms9byPxsl8j8yRn1PDQ/w640-h376/pic1.jpg" width="640" /></a></div><p>By the time Leela activated its queen side rook Stockfish moved both rooks forward, then captured the h pawn and created a passer. The engines traded pawns and exchanged a pair of rooks, Stockfish captured another pawn on the queen side and created a passer there. By move 56 all the black pawns were gone, Stockfish was two pawns up in a RN vs RN endgame. </p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiOavcZIlongpBxO4VZXzD2KFg5aUURc9nsEAIUXp5XtgOU688OU2Zjq5JiZ6LtcQdBiVuBV403U3OfqjkuuP3DI7Obv26fRusCtlkAkXp9GJo8pJZC8A3Jg4DQCraiO3z6yuaEdlcOQXScCFJqyu9diovmLuxZBjREiMNY4FKqFYfiNjsa_HxmfKHkGrQ/s1180/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="693" data-original-width="1180" height="376" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiOavcZIlongpBxO4VZXzD2KFg5aUURc9nsEAIUXp5XtgOU688OU2Zjq5JiZ6LtcQdBiVuBV403U3OfqjkuuP3DI7Obv26fRusCtlkAkXp9GJo8pJZC8A3Jg4DQCraiO3z6yuaEdlcOQXScCFJqyu9diovmLuxZBjREiMNY4FKqFYfiNjsa_HxmfKHkGrQ/w640-h376/pic2.jpg" width="640" /></a></p><p>Stockfish moved its king forward and pushed its pawns slowly. Leela tried to avoid a 7-man position, this only prolonged the game for a few moves before adjudication. There were two white wins in this game pair, Stockfish leads 17-10.</p><p><br /></p>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com0tag:blogger.com,1999:blog-4430065842059358622.post-92130959863106772262023-10-22T23:08:00.001+03:002023-10-22T23:09:25.776+03:00Season 25 superfinal games 41-50<p>After 50 games Stockfish leads 14-8 with 28 draws. Stockfish extended its lead to 6 after two game pair wins. There were 3 drawn game pairs, one of them with two white wins. Stockfish won twice in a queen endgame, Leela seems to be struggling in these, its eval is sometimes low when Stockfish already sees the win in its PV. At the half way point of the match Stockfish is leading by 6 wins, not a huge margin after 25 game pairs played. However so far Leela only won a single game pair, so I would say Stockfish is the clear favorite to win the match.</p><p>Games 41-42 started in the Scandinavian defense, Mieses variation, played in high level human chess. In <a href="https://tcec-chess.com/#div=sf&game=41&season=25">game 41</a> the engines played out a long PV agreement, the black king moved without castling and white castled long. Evals were stable, most minor pieces were exchanged, Stockfish developed its king side rook through the h file. On move 29 the game reached a QRR vs QRR position.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjzrE2JDInd29uO2xhJoJDOZZ-t_chH9j5IARjCQwaq-PdVnWqNc4CTAhzWH_4QTPftE_dprwgdsm5K_jDq01hiavO9F8aLXsO2Z9G4J5c521ENsQ5buJYco2lhhXOUFRoz2iLTczkDvLf-IYRyMsS7RulJI1pnv0dzsK910HqOKE_99tflXH2Qq6iHW9U/s1153/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="696" data-original-width="1153" height="386" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjzrE2JDInd29uO2xhJoJDOZZ-t_chH9j5IARjCQwaq-PdVnWqNc4CTAhzWH_4QTPftE_dprwgdsm5K_jDq01hiavO9F8aLXsO2Z9G4J5c521ENsQ5buJYco2lhhXOUFRoz2iLTczkDvLf-IYRyMsS7RulJI1pnv0dzsK910HqOKE_99tflXH2Qq6iHW9U/w640-h386/pic1.jpg" width="640" /></a></div><p>The engines pushed pawns forward and evals started to increase. After a pawn exchange both engines created a passer on the queen side. All the pieces focused on the black e5 pawn, on move 57 the queens were exchanged.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjRgtyFS5AXOUhlPk08HnQibrBHwMlck8XSvemV132UYS7N1n65SIj8izzMMfUyjtyrtVECv_pjKP-CJRFq54gQCE1HYwthdXgpbXIQuKjSs72jE12mEpVhPVVogTXhJ6BVh7FKox_TJct-AhS5ZIT-2PFKgtaJ3EQSDKUZ4CcOCVsxulDDPljNWEokwNI/s1162/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="694" data-original-width="1162" height="382" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjRgtyFS5AXOUhlPk08HnQibrBHwMlck8XSvemV132UYS7N1n65SIj8izzMMfUyjtyrtVECv_pjKP-CJRFq54gQCE1HYwthdXgpbXIQuKjSs72jE12mEpVhPVVogTXhJ6BVh7FKox_TJct-AhS5ZIT-2PFKgtaJ3EQSDKUZ4CcOCVsxulDDPljNWEokwNI/w640-h382/pic2.jpg" width="640" /></a></p><p>Stockfish gave the e pawn, perhaps to activate its rooks. Leela catured another pawns and pushed two passers forward. Stockfish blocked the passers with its rooks and pushed its passer forward. Leela captured a rook, both engines queened, Leela had the material advantage to force mate.</p><p>In <a href="https://tcec-chess.com/#div=sf&game=42&season=25">game 42</a> the engines repeated game 41 for 40-plys, this time Stockfish did not exchange its last knight. The engines shuffled for a while, then Stockfish moved the g pawn forward and captured a pawn. Evals started to increase, in a series of exchanges the engines reduced to a double rook ending.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiq0_4a5PA8YFQvDgiDLa2_k_8cWLQ_YATYuHCB9Oy8yIr8te1BbN0tMSbcKxRdHJKexJqvmt5NibbtspFDDmqQGnwQJBNlcqoo0jJwDllfhfkhCl9fvoQjuqsZU6AbWDnq0Fu3UQmDyyE0KeQWf64cNv-9neUAlHPweTWl2blHzduCgd_dlgT9XDmKU4A/s1174/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="694" data-original-width="1174" height="378" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiq0_4a5PA8YFQvDgiDLa2_k_8cWLQ_YATYuHCB9Oy8yIr8te1BbN0tMSbcKxRdHJKexJqvmt5NibbtspFDDmqQGnwQJBNlcqoo0jJwDllfhfkhCl9fvoQjuqsZU6AbWDnq0Fu3UQmDyyE0KeQWf64cNv-9neUAlHPweTWl2blHzduCgd_dlgT9XDmKU4A/w640-h378/pic1.jpg" width="640" /></a></div><p>All pawns were passers, Stockfish blocked a captured the black e pawn on the 2nd rank. It had two passers left, with the king support it slowly pushed them forward. Leela tried to avoid a 7-man position but Stockfish forced it when it queened a passer and Leela captured it. There was one white pawn left, the engines continued to play the won 7-man position for more than 30 moves, the game reached a tablebase win on move 135. There were two white wins in this game pair, Stockfish leads 12-8.</p><p>Games 43-44 started with a 22-ply rare sideline of the QGD Orthodox defense, Rubinstein variation. The engines castled in opposite directions, all pieces were on the board and the c file was open. In game 43 after a few moves the engines started a long PV agreement, they exchanged queens and a few minor pieces. Evals came down, Stockfish gave two pawns and the game reached a RB vs RB position. Leela was two pawns up with two doubled pawns, Stockfish had an advanced passer and also had a possibility of perpetual check. Evals were low enough for an early adjudication. </p><p>In <a href="https://tcec-chess.com/#div=sf&game=44&season=25">game 44</a> Leela pushed pawns on the queen side and placed a rook on the open c file. Evals slowly increased, Stockifsh pushed pawns on the king side. In a long PV agreement Leela gave a pawn, opened the queen side further and the black queen joined the attack.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhMl8rBDq6uC_G20hKu0gtlDv6_o4zr5ax0aILvKanL9B3zHhyPOzgghjn1BkIGN5uk7nn8FMNQ19j9X0a0ig83-iCeoW4wJDvbDS_cIwEUEqQ74c02LYGFlVXaJ292phVbTNYhObVs-RBt7h-aOYVE1NDLJPjahtcf8XuO7QvyCNiYDITd8-wwoVszDHc/s1180/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="693" data-original-width="1180" height="376" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhMl8rBDq6uC_G20hKu0gtlDv6_o4zr5ax0aILvKanL9B3zHhyPOzgghjn1BkIGN5uk7nn8FMNQ19j9X0a0ig83-iCeoW4wJDvbDS_cIwEUEqQ74c02LYGFlVXaJ292phVbTNYhObVs-RBt7h-aOYVE1NDLJPjahtcf8XuO7QvyCNiYDITd8-wwoVszDHc/w640-h376/pic1.jpg" width="640" /></a></div><p>Stockfish made sure it had enough pieces to defend b2. After exchanging a pair of rooks Leela's attack appeared less threatening. The engines continued to exchange pieces and reduced to a QB vs QB position on move 47. The white king slowly moved forward, the bishops were exchanged on move 59.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhCOFoqpA28wZE03aC_qS3-JvXEgmy8KhYULyLl9Pis3lqP4Bdjn5oSh9CX_fFeT1GeW9KmVj-lndE_wLX7TaKN7Uq0uezFN-SXICgxnZQa69aJDlArV36Dn9okePGCs79pVW3L5Tca4nrv1l6B4jKpRjMtF3kQmZHxOMmsFfQfY-u5EQbeeAkhFWVR6uo/s1180/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="693" data-original-width="1180" height="376" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhCOFoqpA28wZE03aC_qS3-JvXEgmy8KhYULyLl9Pis3lqP4Bdjn5oSh9CX_fFeT1GeW9KmVj-lndE_wLX7TaKN7Uq0uezFN-SXICgxnZQa69aJDlArV36Dn9okePGCs79pVW3L5Tca4nrv1l6B4jKpRjMtF3kQmZHxOMmsFfQfY-u5EQbeeAkhFWVR6uo/w640-h376/pic2.jpg" width="640" /></a></p><p>Stockfish captured the black b pawn, Leela chased the white king with its queen for a long time. Leela's eval dropped below 1 for a while but then jumped back. On move 102 the white king reached the back rank, Leela started to lose pawns, Stockfish managed to queen a passer and mate. Stockfish wins the game pair, it leads 13-8.</p><p>Games 45-46 started in the KGA Bishop's gambit, Cozio variation. Black was a pawn up, the white king moved without castling and black had an eval advantage. In <a href="https://tcec-chess.com/#div=sf&game=45&season=25">game 45</a> the engines developed their pieces, then Stockfish gave two pawns, opened the e file and placed a pawn facing the white king on the king side. Leela's (negative) eval jumped, Stockfish captured a pawn back and castled long. In a long PV agreement Leela's eval dropped back, the engines exchanged pieces and pawns until only QR vs QR were left on move 36.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjEeaE_Trh9XU1Siy6eujvjCpn_BKYoUXleo7sXITq3BncpS7DXXpSF2gqaJUZqXKQeyyAU9ZpWbjtbeprwrpOYF2ziu-ewS6FkcHgl4v3BPY7MnLl5wT_MUbkunXzbputE3nx1sJN8ExKlWgB5bZhhyphenhyphenX2if4jldaX2A2hSnjFiQZLPwMHh1hvK8SD9vFI/s1161/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="694" data-original-width="1161" height="382" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjEeaE_Trh9XU1Siy6eujvjCpn_BKYoUXleo7sXITq3BncpS7DXXpSF2gqaJUZqXKQeyyAU9ZpWbjtbeprwrpOYF2ziu-ewS6FkcHgl4v3BPY7MnLl5wT_MUbkunXzbputE3nx1sJN8ExKlWgB5bZhhyphenhyphenX2if4jldaX2A2hSnjFiQZLPwMHh1hvK8SD9vFI/w640-h382/pic1.jpg" width="640" /></a></div><p>Leela gave the d pawn, its eval was stable while Stockfish's eval steadily increased as it chased the black king to the center. On move 48 the rooks were exchanged, after a while the black h pawn became a passer after a pawn trade. Leela's eva; continued being low, below -0.5 at times as the game progressed. In some of the moves Leela spent a lot of time thinking, yet its eval did not reflect what Stockfish saw as a clear win. On move 76 Stockfish's eval was already over -95, Leela's eval was -.059.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgRFRTPqlJ9-oD3RIgC_zvXcGtjyocpyXK19a4qhW4DgIvz7uxiwNtjUpyR4mGeMls6XD3Nvpo2hUKHlvJWft0Unr87ahqROED717Y_4llRlSJl1lR5kwBWXLz6g4rThizsxnAcT5zfD-6EF-7jpQrKYYaSF0DG4OUxMlk7-IjPMb4liQvLQFlesnIAE4k/s1167/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="694" data-original-width="1167" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgRFRTPqlJ9-oD3RIgC_zvXcGtjyocpyXK19a4qhW4DgIvz7uxiwNtjUpyR4mGeMls6XD3Nvpo2hUKHlvJWft0Unr87ahqROED717Y_4llRlSJl1lR5kwBWXLz6g4rThizsxnAcT5zfD-6EF-7jpQrKYYaSF0DG4OUxMlk7-IjPMb4liQvLQFlesnIAE4k/w640-h380/pic2.jpg" width="640" /></a></p><p>Leela's eval slowly increased finally when Stockfish was already predicting a 7-man win. On move 94 Stockfish captured a pawn, a frew moves later it queened the passer, then it forced mate.</p><p>In game 46 Leela castled long early and Stockfish attacked the queen side. Stockfish's (negative) eval dropped, it gave a knight for two pawns and exposed the black king. Leela had to walk its king back to the center and Stockfish pushed a passer to the 7th rank. The black king continued to run to h6, Leela's eval dropped as well and Stockfish pushed a second passer on the queen side. Leela lost a rook for one passer, Stockfish gave a rook for a knight on the king side and exposed the black king to checks again. Evals were low enough and the game was adjudicated. Stockfish wins the game pair, it leads 14-8.</p><p>Games 47-48 started with a 23-ply line in the QGD exchange variation. The engines castled in opposite directions, there was only one pair of pawns exchanged, black had an eval advantage. In game 47 Stockfish went a pawn up, (negative) evals came down while the engines exchanged pieces and pawns. On move 28 the game reached a RRB vs RRB position, Leela regained the pawn. Evals were close to 0, after exchanging a pair of rooks the game was adjudicated. In game 48 Leela went a pawn up and pushed pawns on the queen side. Again evals came down as the engines exchanged pieces and pawns. Stockfish regained the pawn, the game reached a QB vs QN position and was adjudicated.</p><p>Games 49-50 started with a 20-ply line in the Robatsch (modern) defense. There were no exchanges and white castled long. In game 49 the engines developed pieces and Stockfish castled long as well. Evals came down as the engines played out a very long PV agreement, several pawns and pieces were exchanged and Leela went a pawn up. After the PVs diverged the engines reduced to a QR vs QR position, Stockfish regained the pawn and it had a passer on the king side. The engines shuffled, Leela wouldn't lower its eval, perhaps since the black king was exposed. It lowered its eval with less than 10 moves left on the 50-move counter, the game was adjudicated. Game 50 started with a 53-ply repeat of game 49. After the PVs diverged Leela regained the pawn, the engines shuffled for a while and then reduced to a RN vs RB position. White was again a pawn up but evals were low and the game was adjudicated.</p><p><br /></p>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com0tag:blogger.com,1999:blog-4430065842059358622.post-54891157758182419572023-10-21T01:31:00.000+03:002023-10-21T01:31:23.261+03:00Season 25 superfinal games 31-40<p>After 40 games Stockfish leads 11-7 with 22 draws. Stockfish extended its lead to 4 wins after winning two game pairs, three game pairs were drawn, one of which had two white wins. In the two game pairs Stockfish won it displayed superior endgame skills. In one game pair the two games reached exactly the same RB vs RB endgame, Stockfish managed to draw as black and win as white. In the other Stockfish won a queen ending which Leela seemed to think was a draw for a long time.</p><p>Games 31-32 started with a 24-ply line in the Ruy Lopez, Open, classical defense, played at the highest level of human games. There was one pawn exchange and all pieces were on the board. In game 31 after two moves the engines started to play out a long PV agreement, exchanging most pieces and reducing to a RBN vs RBN position on move 21. Leela was a pawn up, its eval went up for a for a few moves but then came down. The engines traded pawns until all pawns were passers, 3 white on the queen side and 2 black on the king side. Evals were low, after exchanging more pieces the game was adjudicated. </p><p>In <a href="https://tcec-chess.com/#div=sf&game=32&season=25">game 32</a> Leela's first move was different, the black king was vulnerable and Stockfish placed a bishop on h6. The engines exchanged all knights in the center, Leela gave a pawn and both engines created a passer, evals started to increase slowly. Stockfish gave the pawn back, the engines exchanged a pair of rooks and Stockfish replaced the bishop on h6 with a pawn. In a series of exchanges the engines reduced to a queen ending with white a pawn up.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj4IUggA_jDZhxoErPz-99A2PjD46_0LW-PPsZ30iQPvqZSqwHUQ6BvStSUuqR_Dd2yIXpiXEy2ZdROOz4hMJoQ0yOidUFZvzbEpF6TjRN4cyFFS7U8_u6enR4Wb9zqKd8oMboxAWzr9XBqqolpkNp8dCDue6Tr-_dsg458gRHEATFQz2A52V22snz8098/s1171/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="688" data-original-width="1171" height="376" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj4IUggA_jDZhxoErPz-99A2PjD46_0LW-PPsZ30iQPvqZSqwHUQ6BvStSUuqR_Dd2yIXpiXEy2ZdROOz4hMJoQ0yOidUFZvzbEpF6TjRN4cyFFS7U8_u6enR4Wb9zqKd8oMboxAWzr9XBqqolpkNp8dCDue6Tr-_dsg458gRHEATFQz2A52V22snz8098/w640-h376/pic1.jpg" width="640" /></a></div><p>Stockfish used checks to improve its position while keeping its pawns safe. Leela's eval did not increase at first, it jumped when the white king moved forward. Stockfish saw the win in its eval, it forced a queen exchange on move 82, then it queened and mated. Stockfish wins the game pair, it leads 9-6.</p><p>Games 33-34 started with an 18-ply line in the Ponziani opening, Jaenisch counter attack. The white king side was exposed with the black queen on h3, black had the advantage. In game 33 Stockfish avoided a queen exchange, it castled long while the white king moved without castling. Leela was slow to develop the queen side, though (negative) evals came down. Stockfish created a passer on the king side and pushed it forward while Leela captured a pawn. Stockfish gave a knight and attacked the white king, Leela lost a rook for the passer and the game reached a B vs R ending. Both engines had two pawns on the queen side and Leela had a fortress. Stockfish wouldn't lower its eval for the draw rule, the game was adjudicated only on move 159. In game 34 Leela castled long, the queens were off early and the white king was not in danger. (negative) Evals came down, Stockfish captured pawns on the king side and gave a rook for a bishop. Leela created a passer on the king side and pushed it forward, Stockfish blocked with a rook. In a RBN vs RRN position Stockfish gave two minors for a rook and captured the black passer. Evals were close to 0 and the game was adjudicated. </p><p>Games 35-36 started with a sideline of the Old Indian defense. In game 35 Leela moved its queen forward and captured the b7 pawn, Stockfish tried to trap the white queen. Leela moved a knight forward and captured a second pawn, then gave a rook for a bishop and moved its second knight forward to protect the first knight and to let the queen retreat. Evals came down, there were more exchanges and eventually the engines reduced to a QRB vs QRN position. After exchanging queens the game was adjudicated. In game 36 Stockfish moved its queen forward, it captured two pawns on the queen side and Leela didn't try to stop it. Stockfish exchanged queens, it was two pawns up but its development was slower and its king castled late. Leela moved a rook to the 2nd rank and in a RRB vs RRN position captured one pawn back. Evals came down, the engines continued to exchange pawns and pieces and the game was adjudicated in a rook ending.</p><p>Games 37-38 started with a 32-ply line in the Sicilian Dragon, Yugoslav attack. The engines castled in opposite directions, black was a pawn up and the h file was half open. In <a href="https://tcec-chess.com/#div=sf&game=37&season=25">game 37</a> Stockfish gave a rook for a bishop early, then it gave another rook for a knight and exchanged queens. On move 29 the game reached a RR vs BN position with black 3 pawns up.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhvfeeMqduOheDeTHKhUubKuo09q_au8-b3mQlP6rUvbdw-afWRtZxXu1GGla41EIZT5AFMAbPcdQGIXHSowyISCH_NvOhfy9BC1y_ESIZiPGpld2AOW7kCakDyGdfrJiP4vxD3QNsFwWQggalB8_eOqK_WrrQVC7FWi5SQKBHFDhP4gjIjuNdjESgfk84/s1191/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="693" data-original-width="1191" height="372" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhvfeeMqduOheDeTHKhUubKuo09q_au8-b3mQlP6rUvbdw-afWRtZxXu1GGla41EIZT5AFMAbPcdQGIXHSowyISCH_NvOhfy9BC1y_ESIZiPGpld2AOW7kCakDyGdfrJiP4vxD3QNsFwWQggalB8_eOqK_WrrQVC7FWi5SQKBHFDhP4gjIjuNdjESgfk84/w640-h372/pic1.jpg" width="640" /></a></div><p>Stockfish tried to block files to restrict the white rooks, Leela gave a pawn and opened the queen side. Stockfish captured all the white pawns but Leela moved its rooks forward and captured pawns. Eventually Leela trapped and captured the black bishop, the game ended in a tablebase win.</p><p>In <a href="https://tcec-chess.com/#div=sf&game=38&season=25">game 38</a> the engines exchanged bishops and Stockfish moved its queen to h6. The black king was trapped and Leela moved its queen to help it. Stockfish exchanged a pair of knights and regained the pawn, then the queens were exchanged. Stockfish captured another pawn and created a passer on the king side, on move 31 the game reached a RN vs RB position.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi3mjgyQMCxTZEvfyuNZz9rTpuOD4hNkMY7EES3Zg37igix_R-Gj5DX4XyKkOMa6fLTBq7DWovAVbeRo4NrPmjYtnk7srYBj9MTZ_BU7bPhKCGNdvCvu-xbKmkZK4WCoCW20nelF0b-ieoEysbB14scgWqZz3Q1ldarVnZjnjKPpaRMJrumcjdfc4_xZts/s1182/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="694" data-original-width="1182" height="376" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi3mjgyQMCxTZEvfyuNZz9rTpuOD4hNkMY7EES3Zg37igix_R-Gj5DX4XyKkOMa6fLTBq7DWovAVbeRo4NrPmjYtnk7srYBj9MTZ_BU7bPhKCGNdvCvu-xbKmkZK4WCoCW20nelF0b-ieoEysbB14scgWqZz3Q1ldarVnZjnjKPpaRMJrumcjdfc4_xZts/w640-h376/pic1.jpg" width="640" /></a></div><p>Leela blocked the passer with its king. In a long PV agreement the engines exchanged pawns and Stockfish abandoned its passer, though evals continued to increase. On move 51 the remaining pawns were on the queen side, each engine had 3 pawns, the black pawns were all on dark squares and the white pawns on light squares.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEios1NBD9kAGTh3QMkaeh6sHohvlbanN156Myg38tj0KCcTIWwYcTnfiSGXRCXXR6-mA27jHk3td4CejEjJjhGbce8TtJ20ybBDs4LnQIjv86MEkhqzesZTZ0HSBmpV55xzRr7frWBSZ96BD3gaifDWK7oJnbB3U1ZDKKeAgman6_vrfX_3gs5rsmolyeg/s1167/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="694" data-original-width="1167" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEios1NBD9kAGTh3QMkaeh6sHohvlbanN156Myg38tj0KCcTIWwYcTnfiSGXRCXXR6-mA27jHk3td4CejEjJjhGbce8TtJ20ybBDs4LnQIjv86MEkhqzesZTZ0HSBmpV55xzRr7frWBSZ96BD3gaifDWK7oJnbB3U1ZDKKeAgman6_vrfX_3gs5rsmolyeg/w640-h380/pic2.jpg" width="640" /></a></p><p>Two black pawns were weak and the bishop could not protect them. Stockfish made sure its b3 pawn had enough defenders, slowly it captured black pawns and on move 75 all were captured. Stockfish had two pawns, Leela lost material and the game ended in a tablebase win. There were two white wins in this game pair, Stockfish leads 10-7.</p><p>Games 39-40 started with a 20-ply line in the Semi Slav, accelerated Meran variation. Both queens moved forward on the queen side where a pair of pawns was exchanged. In game 39 the engines played out a long PV agreement, they opened files on the queen side, Stockfish kept its king uncastled. Stockfish gave two pawns and then in a series of exchanges the game reached a RB vs RB position. Leela was two pawns up with no passer and doubled pawns on the queen side. After a while Stockfish managed to captured one of the doubled pawns and formed a strong bishop-pawn pair on the queen side. Evals slowly came down while the engines shuffled, Leela couldn't find a way to improve. There were a few pawn exchanges, Leela was slow in lowering its eval, the game was adjudicated on move 112.</p><p>In <a href="https://tcec-chess.com/#div=sf&game=40&season=25">game 40</a> the engines repeated game 39 for 72 plys, with transpositions and in some cases slightly different moves. The game reached a RB vs RB position with white a pawn up, and with such a long repeat and evals stable and not high it was obvious the game would have the same outcome. On move 53 Stockfish's eval jumped, but after a pawn exchange a few moves later it came back down. On move 73 Stockfish's eval jumped again, this time it kept increasing. Leela's eval remained low for more than 15 moves, the white king managed to move forward through the center and Stockfish created a passer on move 90.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhqYLUK00izae7E8UMCu4YbOj8g92yPEOnohpnURk3fV9Inea0eWmONGBMpkxlb1SzejoZW3oeoMJJrHB324m-OoFEL6n90UGBcZhC1T1GqkJvbm8MaR68wPW0ta_OE7d4cmMIkXx79_Iz7s0bywxFzmAd96PifABbW3_S7_0FbEm7ORey8qQctbtf2q7w/s1183/pic1.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="694" data-original-width="1183" height="376" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhqYLUK00izae7E8UMCu4YbOj8g92yPEOnohpnURk3fV9Inea0eWmONGBMpkxlb1SzejoZW3oeoMJJrHB324m-OoFEL6n90UGBcZhC1T1GqkJvbm8MaR68wPW0ta_OE7d4cmMIkXx79_Iz7s0bywxFzmAd96PifABbW3_S7_0FbEm7ORey8qQctbtf2q7w/w640-h376/pic1.jpg" width="640" /></a></div><p>Leela's eval started to increase while Stockfish already saw the win. Leela captured the two pawns on the king side but Stockfish threatened mate and Leela gave a rook for a bishop. The game ended in a tablebase win with one last white pawn. Stockfish wins the game pair, it leads 11-7.</p><p><br /></p>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com0tag:blogger.com,1999:blog-4430065842059358622.post-49728215996088261692023-10-19T00:58:00.000+03:002023-10-19T00:58:55.983+03:00Season 25 superfinal games 21-30<p>After 30 games Stockfish leads 8-6 with 16 draws. Stockfish's lead is still 2 wins after each engine won one game pair and there were three drawn pairs, one with two white wins. Leela won its first game pair of the match, adding tension to the match since it is not one-sided and the gap is still small. </p><p>Games 21-22 started with 6-ply line in the Scandinavian, Blackburne gambit. In game 21 the engines played out a long PV agreement, developing their pieces and exchanging a few minor pieces. Leela had a pawn majority on the queen side but it didn't find a way to push the pawns safely. Evals came down, the engines shuffled for a long time. After exchanging pieces the draw rule adjudicated the game on move 79. In game 22 again the engines developed their pieces mostly in PV agreement, and most minor pieces were exchanged. Evals slowly came down, the game reached a QRN vs QRB position with white a pawn up. Stockfish gave a pawn and created a passer, after some shuffling it gave another pawn. Evals were close to 0, the engines continued to exchange pieces and the game was adjudicated.</p><p>Games 23-24 started with a 19-ply line in the Sicilian, Scheveningen variation, Keres attack, played in high level human chess. In game 23 the engines castled in opposite directions, in a knight exchange Leela chose to retake with a rook and Stockfish's eval dropped. Stockfish seemed to have the initiative, it was focused on attacking the queen side while Leela blocked and interfered. Evals steadily decreased, Stockfish managed to get a knight to a3 and to open files. It gave a rook for a bishop and moved the queen forward to attack the exposed white king. The game was adjudicated in a QR vs QN position, with perpetual check in the PV.</p><p>In <a href="https://tcec-chess.com/#div=sf&game=24&season=25">game 24</a> again the engines castled in opposite directions, in the same knight exchange Stockfish retook with a bishop. For a few moves Stockfish offered a bishop and Leela refused to take as it would expose its king to attack. In a series of exchanges the engines reduced to a RBN vs RBN position, Stockfish was a pawn up with connected passers on the queen side but evals were low.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjxCeik_mPSM-cgauDIj27U8OSCERUu78AXhh_AN1POmBC9cm5ZRoKxkMwQ22sghkLnttQTdlwX1mJQuO2mC-rt9HPuU2ctfhwTfWtYTMs-thBDuPRFs4DafPy_08c93cZnFAVmDnDew1GnsBVy1og5GJo7PQMZDzGKkjcIgOIjPw_GW4N9tfJtJeffb2U/s1174/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="691" data-original-width="1174" height="376" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjxCeik_mPSM-cgauDIj27U8OSCERUu78AXhh_AN1POmBC9cm5ZRoKxkMwQ22sghkLnttQTdlwX1mJQuO2mC-rt9HPuU2ctfhwTfWtYTMs-thBDuPRFs4DafPy_08c93cZnFAVmDnDew1GnsBVy1og5GJo7PQMZDzGKkjcIgOIjPw_GW4N9tfJtJeffb2U/w640-h376/pic1.jpg" width="640" /></a></div><p>Leela moved its rook forward and captured a pawn, Stockfish's eval started to increase. Stockfish chased the black pieces away and attacked the black king. Leela's eval reacted after 6 moves, the black king had to run forward. After exchanging bishops Stockfish captured two pawns on the king side. Leela had a passer on the king side, Stockfish was only a pawn up but now both evals were over 2.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgsuAPsBukST9JEzB-YnYCT2b1qFlgmpKHrb1o7BCrT5K7psIFbjk2vZXC8jbo4JwTEsTbbtrYFa9GXqmc3VEvzvQS0FEXpurKKRSikVdef2TcqDzKwmlIW8p_oFQYgM9PMxL6W1nDZhztTF2plIm8qCWKYAYobrgGFHM0s2KzvzvE73JK53c5jyQEAALw/s1182/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="691" data-original-width="1182" height="374" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgsuAPsBukST9JEzB-YnYCT2b1qFlgmpKHrb1o7BCrT5K7psIFbjk2vZXC8jbo4JwTEsTbbtrYFa9GXqmc3VEvzvQS0FEXpurKKRSikVdef2TcqDzKwmlIW8p_oFQYgM9PMxL6W1nDZhztTF2plIm8qCWKYAYobrgGFHM0s2KzvzvE73JK53c5jyQEAALw/w640-h374/pic2.jpg" width="640" /></a></p><p>Stockfish blocked the black passer with its rook and slowly pushed its queen side passers. Leela traded its passer with the white f pawn, and pushed its e passer forward. Stockfish captured the passer with its knight on the 2nd rank, Leela did not take back to avoid a 7-man position. This only delayed the end by a few moves after Stockfish queened a passer. Stockfish wins the game pair, it leads 7-4.</p><p>Games 25-26 started with an 18-ply line in the Sicilian Nimzowitsch variation. Both queens were out on the queen side, white was a pawn up with a passer on d6. In <a href="https://tcec-chess.com/#div=sf&game=25&season=25">game 25</a> Leela gave a pawn and Stockfish castled long. Stockfish captured the white passer but lost a knight. The engines played out a long PV agreement where the queens were traded and the result was a BN vs R imbalance with high evals.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjMlvWqomBFLDbjmfOIiUJ6fEOxM441v0jfWJfN3N8lP77vIYQOtdykFv0f3c89wLonE7ckMvM0S4HIFEmiYGIkdCP-x7NJoKCh7TEqVQGF2aGKbPAfc_wqLl87Y7Ue6ZRcjAHy8EtHFulWQgmq1J0_P_zqAfQIfHrgBQQB1TE1FECJwSTfIVOyXI-O5p8/s1161/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="694" data-original-width="1161" height="382" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjMlvWqomBFLDbjmfOIiUJ6fEOxM441v0jfWJfN3N8lP77vIYQOtdykFv0f3c89wLonE7ckMvM0S4HIFEmiYGIkdCP-x7NJoKCh7TEqVQGF2aGKbPAfc_wqLl87Y7Ue6ZRcjAHy8EtHFulWQgmq1J0_P_zqAfQIfHrgBQQB1TE1FECJwSTfIVOyXI-O5p8/w640-h382/pic1.jpg" width="640" /></a></div><p>Stockfish formed a pawn line on the king side and tried to protect the pawns, Leela exchanged a pair of pawns and captured one, creating a passer. After exchanging a pair of rooks Leela traded a knight for the black bishop, leaving a BB vs R ending.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgs4uMULjw_xHjeH2mVvw-7kgw2i5b94ny66GNQnzAXAbJWh6t1KGGDsZuysxNI_6ClDa-rUmXpW2xrkdg2fqn9FVjRqC_5bUFnmEB3Oj2oxTpChXtMAeCswF_se2JTXfHI8jxE3qDtvbVpNuM7jeyHUH4rZ6Vbce_V4P6DsLLrKi0xtmOUj1qWb9b3jc0/s1159/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="697" data-original-width="1159" height="384" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgs4uMULjw_xHjeH2mVvw-7kgw2i5b94ny66GNQnzAXAbJWh6t1KGGDsZuysxNI_6ClDa-rUmXpW2xrkdg2fqn9FVjRqC_5bUFnmEB3Oj2oxTpChXtMAeCswF_se2JTXfHI8jxE3qDtvbVpNuM7jeyHUH4rZ6Vbce_V4P6DsLLrKi0xtmOUj1qWb9b3jc0/w640-h384/pic2.jpg" width="640" /></a></p><p>Both engines had a passer but the bishop pair was very strong. Leela captured the black pawns on the king side and blocked the black passer. The white passers were unstoppable, the game was adjudicated after Leela queened.</p><p>In <a href="https://tcec-chess.com/#div=sf&game=26&season=25">game 26</a> both kings stayed in the center and the black queen retreated. Stockfish lost its passer and it gave another pawn, giving Leela a passer in the center. Evals rapidly increased, Leela captured another pawn but lost a rook by a knight fork. </p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjqcP3Ohyphenhyphenfg_pbmZB79kRbDu73L2N62RXVC-hco97dpTs6a4fsWIPI_8wJOD0QlwrEX0THApQJbfaI_6ez9E-9HQDYe6AWbu6ssXTbB_ffK-vtJbp7MbtnC3Hj8KgueOWU7_l11gm2xFzhkBJvCcUEGi6ghum02Wt4TaYwSVrbbgrfNkp4K2YYg9V1C8HI/s1180/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="696" data-original-width="1180" height="378" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjqcP3Ohyphenhyphenfg_pbmZB79kRbDu73L2N62RXVC-hco97dpTs6a4fsWIPI_8wJOD0QlwrEX0THApQJbfaI_6ez9E-9HQDYe6AWbu6ssXTbB_ffK-vtJbp7MbtnC3Hj8KgueOWU7_l11gm2xFzhkBJvCcUEGi6ghum02Wt4TaYwSVrbbgrfNkp4K2YYg9V1C8HI/w640-h378/pic1.jpg" width="640" /></a></div><p>Leela's compensation for the rook was the trapped knight in the corner as well as the white rook and bishop on the king side that could hardly move. Leela pushed the passer to d3 and tightened the trap. Stockfish captured the h pawn with its queen and freed its corner knight. It pushed the h pawn and opened a way out for its rook. In a series of exchanges the engines reduced to a RRB vs RB position. </p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhTwVDU5KyoiayeDkHZiNvaI05NbuK7Tf-QjGhvdlL1ocINJG0JMPAuX9qOivGhTDyVhFIZS0HEMaG1oQGTwZmusB9AOhebbVYSAoiYBBBHuxnbIbxBwVf1dLR8slG-reZyB7ABrrkHPXELPYQBxuBwkdy0jZ71-SHlRXdZeDWeNrgRD_4e7Ac_25LdOqk/s1176/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="696" data-original-width="1176" height="378" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhTwVDU5KyoiayeDkHZiNvaI05NbuK7Tf-QjGhvdlL1ocINJG0JMPAuX9qOivGhTDyVhFIZS0HEMaG1oQGTwZmusB9AOhebbVYSAoiYBBBHuxnbIbxBwVf1dLR8slG-reZyB7ABrrkHPXELPYQBxuBwkdy0jZ71-SHlRXdZeDWeNrgRD_4e7Ac_25LdOqk/w640-h378/pic2.jpg" width="640" /></a></p><p>Leela had connected passers on the 2nd and 3rd ranks but they were blocked, and Stockfish had an extra rook. Stockish gave a rook for a bishop and captured both passers, the game ended in a tablebase win. There were two white wins in this game pair, Stockfish leads 8-5.</p><p>Games 27-28 started with a 20-ply sideline of the French, Tarrasch closed variation. In game 27 both kings stayed in the center and there were many early exchanges. Stockfish had a passer in the center, after exchanging queens Leela created a passer on the king side. Evals steadily decreased, Stockfish castled late and blocked the white passer with its king. The game reached a RBB vs RBN position, Stockfish captured the white passer and Leela moved the rook to the 7th rank. Evals were low enough for the draw rule, Stockfish gave a rook for a bishop and the game was adjudicated. Game 28 started with a 30-ply repeat of game 27 with a transposition. Stockfish pushed pawns on the king side and created connected passers there. Leela walked its king to block together with a knight, Stockfish traded a bishop for the knight and the game reached a RRB vs RRB position. The engines shuffled for a while with evals close to 0, after exchanging a pair of rooks the game was adjudicated.</p><p>Games 29-30 started with a rare sideline of the semi Slav, accelerated Meran variation. In <a href="https://tcec-chess.com/#div=sf&game=29&season=25">game 29</a> the engines formed a diagonal pawn wall that blocked the center and most of the queen side. The engines castled in opposite directions and evals were stable. A few pawn exchanges opened the g file, most of the black pieces moved to the king side to protect the king. All pieces were on the board, the engines shuffled for a while and then Stockfish captured the h pawn on move 38.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjfwc8icGiexyKzt9r_DbX5aEe2KVlHC_nmGivq2iH7Ovp8Qkd1IYWJljAeqvhrx9RhhSsaSY4YjgZCcN9CqH19sQUcqj58iIbQQTPAHcUIwifpmq4o5YDpvQqNr6w7-POgt9nlpCqJ0SDGG6mj3mmnCsVbuhOGuCCISUDMHyyqWxI0WEzxW2ZvxE8Ocvs/s1167/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="697" data-original-width="1167" height="382" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjfwc8icGiexyKzt9r_DbX5aEe2KVlHC_nmGivq2iH7Ovp8Qkd1IYWJljAeqvhrx9RhhSsaSY4YjgZCcN9CqH19sQUcqj58iIbQQTPAHcUIwifpmq4o5YDpvQqNr6w7-POgt9nlpCqJ0SDGG6mj3mmnCsVbuhOGuCCISUDMHyyqWxI0WEzxW2ZvxE8Ocvs/w640-h382/pic1.jpg" width="640" /></a></div><p>With two open files on the king side Stockfish slowly walked its king to the center. Leela's eval increased and it captured the a pawn, Stockfish was less convinced but it had very little time left to think. The engines exchanged all major pieces, Leela captured another pawn and Stockfish tried to hold its position but its eval increased as well. Leela created an advanced passer on the queen side, the engines reduced to a BBN vs BNN position on move 73.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjTevRVFXcze8B3Jw-jMFZ67FyLAV-KTfwS9nokXeCkRknepNhGDHI1WlAuNVG00ZommQxHGP5TwBST7vbtaimhqrrZawAaDTx3vpwBScgsC6ULhcICHSOHXnJlvQrP2ezg7x9UBLDChIlKV_CBlAvYWfGuelkNshtvvAnp_gQ7J3eHaoL1Qk_gnjb1HFQ/s1171/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="694" data-original-width="1171" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjTevRVFXcze8B3Jw-jMFZ67FyLAV-KTfwS9nokXeCkRknepNhGDHI1WlAuNVG00ZommQxHGP5TwBST7vbtaimhqrrZawAaDTx3vpwBScgsC6ULhcICHSOHXnJlvQrP2ezg7x9UBLDChIlKV_CBlAvYWfGuelkNshtvvAnp_gQ7J3eHaoL1Qk_gnjb1HFQ/w640-h380/pic2.jpg" width="640" /></a></p><p>Stockfish's defense collapsed, Leela's pieces moved forward and it managed to capture the black pawns on the queen side. Leela was two pawns up, the white king moved forward and Stockfish couldn't stop the passers. Leela queened and mated.</p><p>In game 30 both engines castled short, instead of a pawn wall the engines exchanged pawns and opened the board. Evals came down, the engines exchanged pieces until the game reached a queen ending. Stockfish was a pawn up but with all pawns on the king side. Evals were low enough and the game was adjudicated. Leela wins the game pair, Stockfish leads 8-6.</p><p><br /></p>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com0tag:blogger.com,1999:blog-4430065842059358622.post-46447492508517390472023-10-17T01:12:00.000+03:002023-10-17T01:12:16.319+03:00Season 25 superfinal games 11-20<p>After 20 games Stockfish leads 6-4 with 10 draws. Stockfish won a second game pair and increased its lead. There were 4 drawn game pairs, 3 with two draws and one with two wins. The Leela version playing in the superfinal seems to be closer in strength to Stockfish than the version that played in the premier division. Leela still has not been able to win a game pair. </p><p>Games 11-12 started with a sideline of the English opening, Great Snake variation. In game 11 the engines played a long PV agreement with all pieces on the board and only one pawn exchange after the start. Evals came down, after move 25 Stockfish gave two pawns and then there was a series of exchanges and the game reached a RB vs RB position with white a pawn up. Leela captured a pawn and created two passers on the king side. Stockfish managed to keep the white king away, after some shuffling Stockfish captured one of the passers. Leela's eval came down enough for the draw rule. Game 12 started with a 22-ply repeat of game 11. Stockfish concentrated on the center, it gave a pawn and opened files, then placed its major pieces there. Evals came down, in a series of exchanges Stockfish regained the pawn. The game reached a RBN vs RBN position, after the rooks were exchanged the game was adjudicated.</p><p>Games 13-14 started with a French, Tarrasch variation played in high level human chess. In game 13 Stockfish surprised Leela for a few moves, at first Leela's eval increased as if it thought Stockfish's moves were inaccurate. There were only a few exchanges, Stockfish kept its king in the center. On move 20 Stockfish's eval dropped, Leela's eval dropped after thinking for 8 minutes. In a series of exchanges the engines reduced to a RN vs RB position with white a pawn up. The engines traded pawns, Leela created connected passers on the king side and Stockfish had a passer in the center. Stockfish gave the bishop for the 2 white passers, Leela had one pawn left. Leela shuffled to avoid a 7-man draw, eventually it lowered its eval and the game was adjudicated.</p><p>In <a href="https://tcec-chess.com/#div=sf&game=14&season=25">game 14</a> Leela castled its king, its eval was low after the start. There were a few pawn and minor piece exchanges, then Stockfish sacrificed a bishop and exposed the black king. Leela's eval jumped, then slowly decreased. Stockfish threatened the black king with its pieces and its eval increased, Leela was satisfied with its defense. On move 28 leela thought for more than 8 minutes and the eval drop suggested it thought that it was safe.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj31mmVQdhrGbys91gNr2jac_ONU5sUF7QaaKRg51V3J9NQzDBnpaz-klcGhg4N3VE69aebbZuu2iIzMLHkUP3JJb7quEFVK2qfrg8jwcdqfETpkgB-GYf1TDTaxoJGirABnx_XgmrHrL5jDGoyjDNiCxDFhnmyyoKfincjjYNDSi3KZKRU6HMbR6pPZTg/s1171/pic1%20-%20Copy.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="697" data-original-width="1171" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj31mmVQdhrGbys91gNr2jac_ONU5sUF7QaaKRg51V3J9NQzDBnpaz-klcGhg4N3VE69aebbZuu2iIzMLHkUP3JJb7quEFVK2qfrg8jwcdqfETpkgB-GYf1TDTaxoJGirABnx_XgmrHrL5jDGoyjDNiCxDFhnmyyoKfincjjYNDSi3KZKRU6HMbR6pPZTg/w640-h380/pic1%20-%20Copy.jpg" width="640" /></a></div><p>Stockfish played Rd2, seems like a small defensive move, I don't know, but not what Leela expected. Leela thought for almost 15 minutes and its eval jumped to 3. The PVs agreed, there was a series of exchanges and Stockfish gave checks. The end result on move 44 was a QR vs QRN position with white 4 pawns up. </p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiKgh-dmk4keED_KtBf3aTJSZduu6og3UzMN7f00dwjqvA3E_p0vcNmEAHyy0A3j1hyT1uaqZOmBhRH_TvruAZqO9Jz-Y8tJBgS0ok-lDQXmI1ygC0_kRUnZC3byPfePIjNyTFvo9tFHYOYGftnGLlVRG0emqLfEEuPvLwsGlVdS7UZ_gQDJy6r-b1APx4/s1182/pic2%20-%20Copy.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="694" data-original-width="1182" height="376" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiKgh-dmk4keED_KtBf3aTJSZduu6og3UzMN7f00dwjqvA3E_p0vcNmEAHyy0A3j1hyT1uaqZOmBhRH_TvruAZqO9Jz-Y8tJBgS0ok-lDQXmI1ygC0_kRUnZC3byPfePIjNyTFvo9tFHYOYGftnGLlVRG0emqLfEEuPvLwsGlVdS7UZ_gQDJy6r-b1APx4/w640-h376/pic2%20-%20Copy.jpg" width="640" /></a></p><p>Stockfish gave checks, protected its king and slowly pushed the h passer forward. Leela exchanged rooks but couldn't prevent a queening and the game ended in mate. Stockfish won the game pair, it leads 5-3.</p><p>Games 15-16 started with a sideline of the Sicilian, Sozin attack variation. Game 15 started with a long PV agreement, Leela castled long, Stockfish pushed the b pawn but couldn't open the queen side. Leela captured a pawn and the engines reduced to a double rook ending. Evals came down as the engines traded pawns, after exchanging a pair of rooks the game was adjudicated. Game 16 started with an 18-ply repeat of game 15. A series of exchanges reduced to a RRB vs RRB position and Stockfish went a pawn up. Evals came down as the engines traded pawns, after exchanging bishops Leela's eval slowly decreased and 15 moves later the game was adjudicated.</p><p>Games 17-18 started with a rare sideline of the French Winawer, poisoned pawn variation where black defends the g7 pawn with a knight on f5. In game 17 Leela exchanged a bishop for the defending knight and Stockfish moved its king to protect the g7 pawn, blocking its king side rook. Leela captured a pawn, by the time Stockfish freed its rook both engines had a passer on the queen side. The game reached a RRB vs RRB position, the engines traded a pair of rooks and captured both passers, then Leela captured two pawns. Despite being two pawns up Leela couldn't find a way to improve, evals came down and the game was adjudicated. In game 18 Stockfish left the g7 pawn alone, captured a pawn on the queen side and created a passer. Queens were exchanged and evals came down, Leela captured the white passer on the 7th rank. The engines traded pawns and reduced to a RBN vs RBN position. After exchanging rooks the engines shuffled until evals were low enough for the draw rule.</p><p>Games 19-20 started with a rare 6-ply sideline of the Philidor defense. In <a href="https://tcec-chess.com/#div=sf&game=19&season=25">game 19</a> Stockfish gave a pawn and developed its queen early. The engines played out a long PV agreement, Leela kept its king in the center, there were many early exchanges and the game reached a RRB vs RRB position on move 21. Evals were stable but started to increase after move 27, the engines exchanged a pair of rooks and evals were around 2.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjhB2FvgId53lo-iVhKh835rGutIgStm9_hdoSbp6IWEzR1Im1nf6IAfxcVTetOY3-8mh9Z9EpQK1T3EU0OexOlfwimghqWY2ZQ04UkoKiSgEdGHUQZC0eV8kFp82ma3lPOybZe0IPuaH3aLhMLuhleCGSSl84CbGLuBKKOKSZVfvhdP5Ek_jOPGG1sTfU/s1165/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="697" data-original-width="1165" height="382" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjhB2FvgId53lo-iVhKh835rGutIgStm9_hdoSbp6IWEzR1Im1nf6IAfxcVTetOY3-8mh9Z9EpQK1T3EU0OexOlfwimghqWY2ZQ04UkoKiSgEdGHUQZC0eV8kFp82ma3lPOybZe0IPuaH3aLhMLuhleCGSSl84CbGLuBKKOKSZVfvhdP5Ek_jOPGG1sTfU/w640-h382/pic1.jpg" width="640" /></a></div><p>Leela created a passer in the center and supported it with its bishop. Stockfish captured pawns on the queen side and Leela captured pawns on the king side. Leela gave its center passer and replaced it with a passer on the king side. </p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgWbf3ZJsRAo-tdlfnuHxmMqd5xctuf1i5NbgDxMmXpRRrfH_l7bkUiQ8DafiqA-Ry3rxsfknu2hGgBeBaq397Fd2NX1nox0lZXqde9n3l8tkzblkwgvMQb05OgfjtfrabhpEVpyaSJDEd0VxAV_7Fy_-vWR9yskyqvWb_pTMErPDuVsKRBdFoomIJDWMc/s1167/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="696" data-original-width="1167" height="382" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgWbf3ZJsRAo-tdlfnuHxmMqd5xctuf1i5NbgDxMmXpRRrfH_l7bkUiQ8DafiqA-Ry3rxsfknu2hGgBeBaq397Fd2NX1nox0lZXqde9n3l8tkzblkwgvMQb05OgfjtfrabhpEVpyaSJDEd0VxAV_7Fy_-vWR9yskyqvWb_pTMErPDuVsKRBdFoomIJDWMc/w640-h382/pic2.jpg" width="640" /></a></p><p>Stockfish couldn't stop the white passers advancing, Leela queened and mated.</p><p>In <a href="https://tcec-chess.com/#div=sf&game=20&season=25">game 20</a> Leela gave a pawn and castled long, Stockfish gave a bishop for two pawns and exposed the black king. The white queen move forward to the queen side facing the exposed king.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjcRWXLC-jVt127Jkzw5QpdXwon33UO5kx4wD7y9zMUahanyQzDhpZlsfwAZEt1MTHL_SsHhOXHBm_59gJwX_1AqSEfi9dlANXjXNJ1gUxnTZzqG728hWtJ1f7UJzRtzuEKU0872NnR_RiaWCTPX__pOPBiLTpSGnecZEbsxGTwwJWmx_8ZwlLl6yHuT-0/s1180/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="694" data-original-width="1180" height="376" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjcRWXLC-jVt127Jkzw5QpdXwon33UO5kx4wD7y9zMUahanyQzDhpZlsfwAZEt1MTHL_SsHhOXHBm_59gJwX_1AqSEfi9dlANXjXNJ1gUxnTZzqG728hWtJ1f7UJzRtzuEKU0872NnR_RiaWCTPX__pOPBiLTpSGnecZEbsxGTwwJWmx_8ZwlLl6yHuT-0/w640-h376/pic1.jpg" width="640" /></a></div><p>The white knight on f3 crossed the board to b5 and joined the attack. Leela traded a bishop for the knight, in a series of exchanges the engines reduced to a RN vs RNN position with white 4 pawns up on move 33.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEitwyZ4faAPGzcBNyYPpDxaBplnNDz5o9uY7Bxvn1q-IcMqxs7VvQZeqsV_bv6yTPrFe5MCzkfdsej8qZqrijevczgV0Bcjgko0OhFNbqo1r0yybTnhxfWT8eQTrnxJ2PC5HM4SzMCmZcdJJP121VOKAuk9fxIQsKPCaiDrYRnAXI1cCUeW4rGPcy8D0Lw/s1177/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="697" data-original-width="1177" height="378" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEitwyZ4faAPGzcBNyYPpDxaBplnNDz5o9uY7Bxvn1q-IcMqxs7VvQZeqsV_bv6yTPrFe5MCzkfdsej8qZqrijevczgV0Bcjgko0OhFNbqo1r0yybTnhxfWT8eQTrnxJ2PC5HM4SzMCmZcdJJP121VOKAuk9fxIQsKPCaiDrYRnAXI1cCUeW4rGPcy8D0Lw/w640-h378/pic2.jpg" width="640" /></a></p><p>The endgame was slow. Stockfish focused on the king side first, it traded pawns and exchanged a pair of knights, all the black pawns were eliminated and only the white h pawn remained on the king side. The white king moved forward and protected the queen side pawns, Stockfish slowly pushed the h pawn forward. Leela captured the h pawn on the 6th rank, its king was trapped in the corner and Stockfish mated with its pawns. There were two white wins in this game pair, Stockfish leads 6-4.</p><p><br /></p>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com0tag:blogger.com,1999:blog-4430065842059358622.post-45341116100616106442023-10-15T01:56:00.001+03:002023-10-15T01:56:39.345+03:00Season 25 superfinal games 1-10<p>After 10 games Stockfish leads 4-3 with 3 draws. The match started with 3 game pairs with a win for both engines, an exciting start to the match. The first draw was in game 7, Stockfish won the reverse and the 4th game pair was the first decisive one. The 5th game pair ended in two draws.</p><p>The opening book was created by Jeroen Noomen, details can be found <a href="http://blogchess2016.blogspot.com/2023/09/tcec-25-superfinal-book-re-engineering.html">here</a>. Most of the openings were taken from games of chess masters of the past.</p><p>Games 1-2 started with a 24-ply line in the Queen's Indian defense, Kasparov variation. In <a href="https://tcec-chess.com/#div=sf&game=1&season=25">game 1</a> Leela pushed a pawn to h6, Stockfish grabbed a pawn on the queen side, Leela regained the pawn and exchanged queens in the center. The game reached a RRN vs RRB position on move 27, evals started to increase and the engines exchanged all rooks.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiS1vBLPfz16tcwE0bNrzc2CZNh-ykX3-jm_NdQZNiKeVFNOzmDN8FIHSBQ0UOhjRvUYljRt_6sitkvC5DclKBio_5je_v59su9gFUoel93umLiSD_QTjRGsDzBFip6nSi164AB_HC9Z23PCaK0XAaFE92AzCcQvf2fEhrG0nnylW-n_umqXTCnWSm9EvU/s1168/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="697" data-original-width="1168" height="382" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiS1vBLPfz16tcwE0bNrzc2CZNh-ykX3-jm_NdQZNiKeVFNOzmDN8FIHSBQ0UOhjRvUYljRt_6sitkvC5DclKBio_5je_v59su9gFUoel93umLiSD_QTjRGsDzBFip6nSi164AB_HC9Z23PCaK0XAaFE92AzCcQvf2fEhrG0nnylW-n_umqXTCnWSm9EvU/w640-h382/pic1.jpg" width="640" /></a></div><p style="clear: both; text-align: left;">The black bishop had only a few pawns it could target and its own pawns restricted its movement. Leela created passers on both sides of the board and blocked a black passer on the 2nd rank. The black king couldn't defend against all the white passers, Leela queened and won.</p><p>In <a href="https://tcec-chess.com/#div=sf&game=2&season=25">game 2</a> Stockfish also pushed a pawn to h6, there were many early exchanges that opened the board. The game reached a RRB vs RRN position on move 26, the engines exchanged a pair of rooks and traded pawns. The white king moved forward and both engines created a passer on the queen side.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjyeTK14D7KyHUXNfzPW3kITp-4vL4e_zlGAO6J9BudPoR4l5_8OXcKLF6jXw6lHeMInTLt6QiyjOGb2K3pc5-KBSeSGI_ruJ6klaRm2VGzrnj1k0Ns1cKZG3GArJslSLicchNKgEN4tF2csMGv3xvpt-i6Ynum6CEmLFzMyzOkvosl_jcdACa1S83wZZs/s1180/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="694" data-original-width="1180" height="376" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjyeTK14D7KyHUXNfzPW3kITp-4vL4e_zlGAO6J9BudPoR4l5_8OXcKLF6jXw6lHeMInTLt6QiyjOGb2K3pc5-KBSeSGI_ruJ6klaRm2VGzrnj1k0Ns1cKZG3GArJslSLicchNKgEN4tF2csMGv3xvpt-i6Ynum6CEmLFzMyzOkvosl_jcdACa1S83wZZs/w640-h376/pic2.jpg" width="640" /></a></p><p>Stockfish blocked the black king away from the queen side. After exchanging rooks the black king moved to help, Stockfish protected its passer and captured the black passer. The white king switched to the queen side and captured pawns there, the game ended in a tablebase win. There were two white wins in this game pair, the score is 1-1.</p><p>Games 3-4 started with a sideline of the KID Saemisch variation. In <a href="https://tcec-chess.com/#div=sf&game=3&season=25">game 3</a> there were many exchanges after the start with long PV agreements, evals were mostly stable. Leela captured a pawn and created connected passers on the queen side, after queens were exchanged Stockfish moved a pawn to interfere with one of the passers through a capture. On move 33 the game reached a RN vs RB position. </p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhkUJLkTgk45IIYlIxDJqv_D9DOqplKy2N4MoSs8JqurYbFHBY07FI4a626u_yHn3lehAlSS23U1_c5j-Jbqr7aNnu1iMShDcUb2dacfky9Tl2LgdLFljxTC9sLNq26xpOiPlUqjTnNZ0xewQPvuQenEsJgxFbk83wldOtMi2vWS24_aDdZd9QuV2W85FQ/s1177/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="699" data-original-width="1177" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhkUJLkTgk45IIYlIxDJqv_D9DOqplKy2N4MoSs8JqurYbFHBY07FI4a626u_yHn3lehAlSS23U1_c5j-Jbqr7aNnu1iMShDcUb2dacfky9Tl2LgdLFljxTC9sLNq26xpOiPlUqjTnNZ0xewQPvuQenEsJgxFbk83wldOtMi2vWS24_aDdZd9QuV2W85FQ/w640-h380/pic1.jpg" width="640" /></a></div><p>Evals started to increase, Leela pushed the a passer while Stockfish created a doubled passer in the center. Leela gave its a passer but captured more pawns and created passers on both sides of the board.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj2BVbqBiywXpbkm5N9RZS6Q48j2pi8TbN8soLh6Ly-840SIWBey7OSesjgbKmCgIrIMWSsLWaoqqo_fn0LmG8lnb3HNmS5j_-4sM5VSqDkpD_ZtZ-mJIGy9WrEFtbrkQdLfsjuOIdUqgvot6XUNDH4NdephniqPti6ZpOfY9Ev8UZCj8kudoslYdpLM10/s1177/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="700" data-original-width="1177" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj2BVbqBiywXpbkm5N9RZS6Q48j2pi8TbN8soLh6Ly-840SIWBey7OSesjgbKmCgIrIMWSsLWaoqqo_fn0LmG8lnb3HNmS5j_-4sM5VSqDkpD_ZtZ-mJIGy9WrEFtbrkQdLfsjuOIdUqgvot6XUNDH4NdephniqPti6ZpOfY9Ev8UZCj8kudoslYdpLM10/w640-h380/pic2.jpg" width="640" /></a></p><p>Leela slowly pushed its passers forward, the connected passers on the king side supported each other and eventually one promoted to a queen. Ten moves later the game ended in a tablebase win.</p><p>In <a href="https://tcec-chess.com/#div=sf&game=4&season=25">game 4</a> Stockfish kept its king in the center and opened the g file. Most pieces stayed on the board, evals increased steadily. Leela gave a rook for a bishop and tried to protect its exposed king with pieces.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhY_NM9nK0fUozuK5Yam-MtFMRh733vt3wb30e9ijrHijAJdkDBCJwcvvr1xflTp-nKl_2y9bXGZt2GghXUaChSy2DTtHw_f4_NDfChvn-UrD_CKKuwZVMLopROXJLT9i0M5fZDCl3fENxbpizopPqKAbuqR6U7zTiTjShY7VXEay8rViVFcU9FJgcse98/s1165/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="694" data-original-width="1165" height="382" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhY_NM9nK0fUozuK5Yam-MtFMRh733vt3wb30e9ijrHijAJdkDBCJwcvvr1xflTp-nKl_2y9bXGZt2GghXUaChSy2DTtHw_f4_NDfChvn-UrD_CKKuwZVMLopROXJLT9i0M5fZDCl3fENxbpizopPqKAbuqR6U7zTiTjShY7VXEay8rViVFcU9FJgcse98/w640-h382/pic1.jpg" width="640" /></a></div><p>Leela tried to counter with a threat on the f file, Stockfish kept the f3 pawn safe to protect its king. Stockfish offered a rook for a bishop but Leela thought it would weaken its defense. After a few moves Stockfish forced the trade and captured a pawn, the engines reduced to a NN vs BN position on move 45. </p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg2XadavM8Wd7vL2O1miuvAze8nlQufHOqy7A0SvtMrEnyTcDSKglx1qP6jLnaVF3HAR5_12uVamoHiTK8pBgAROglbhXnXF919crsLQSBaclilGhXdhQCl0HlCeYRdoirKLfXUxkv2N3GwyyWOi0mlqR0mz6xERArsMauZEBgoXTMPoSpnROz8h_tuMes/s1180/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="693" data-original-width="1180" height="376" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg2XadavM8Wd7vL2O1miuvAze8nlQufHOqy7A0SvtMrEnyTcDSKglx1qP6jLnaVF3HAR5_12uVamoHiTK8pBgAROglbhXnXF919crsLQSBaclilGhXdhQCl0HlCeYRdoirKLfXUxkv2N3GwyyWOi0mlqR0mz6xERArsMauZEBgoXTMPoSpnROz8h_tuMes/w640-h376/pic2.jpg" width="640" /></a></p><p>Stockfish was a pawn up with a passer, it was confident it was winning but the endgame was long. Leela blocked the passer with its king and protected its isolated pawns. After 15 moves Leela chose to give its bishop for the passer and another pawn. The black king raced to the queen side, there Stockfish trapped it and mated with two knights. There were two white wins in this game pair, the score is 2-2.</p><p>Games 5-6 started with a 22-ply line in the Vienna gambit, Fraser-Minckwitz defense, with black a pawn up and white unable to castle, an advantage for black. The black king castled long and there was a white pawn on a6. In <a href="https://tcec-chess.com/#div=sf&game=5&season=25">game 5</a> Stockfish gave 3 pawns and opened the king side, with the white king exposed on g3. More pieces joined the attack and (negative) evals increased. The engines exchanged all rooks and Stockfish equalized material, only QNN vs QBN were left on move 33.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiPm-ShBft1h2k_gMk26O2GCn400EmIPQIqKTFGGRWMR2kDyC5LLAs5IVd4GLzq60xm-vahHMOL6Cp5K62gX10YfuywdbOSvYBdBjHCqsnvOHjm2TYzjtJIA6pYyrOXjm5urmidQzYNjE7W9rzAoJk4b9c_FNR7jVdkO-NBFkUNHvwzYvtSxtP7IhyphenhyphenS2ak/s1171/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="691" data-original-width="1171" height="378" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiPm-ShBft1h2k_gMk26O2GCn400EmIPQIqKTFGGRWMR2kDyC5LLAs5IVd4GLzq60xm-vahHMOL6Cp5K62gX10YfuywdbOSvYBdBjHCqsnvOHjm2TYzjtJIA6pYyrOXjm5urmidQzYNjE7W9rzAoJk4b9c_FNR7jVdkO-NBFkUNHvwzYvtSxtP7IhyphenhyphenS2ak/w640-h378/pic1.jpg" width="640" /></a></div><p>Stockfish had a pawn majority on the queen side, it pushed the a and b pawns forward and created a passer. Leela blocked the passer and had to defend against threats to its king and queen. By the time Leela managed to capture the passer Stockfish captured the white g pawn. </p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjyI40il4viXMouV5PUthqx4dL8_ehFL0-OfQ2Lj3bVIVe4lAlSMSHotcdglRfRaeL_ZtmlxMUz0VcZxFK1YF0bm57-S4LPErHoAAUzkP7ur-TkhyphenhyphenBr9JnDvmiKBhogF_cq2J4CHpl3oQXqkBxD2b9YdBYG5qu3CBY74ocA3w2FjYEaul_k_KxV6aPUrv8/s1168/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="691" data-original-width="1168" height="378" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjyI40il4viXMouV5PUthqx4dL8_ehFL0-OfQ2Lj3bVIVe4lAlSMSHotcdglRfRaeL_ZtmlxMUz0VcZxFK1YF0bm57-S4LPErHoAAUzkP7ur-TkhyphenhyphenBr9JnDvmiKBhogF_cq2J4CHpl3oQXqkBxD2b9YdBYG5qu3CBY74ocA3w2FjYEaul_k_KxV6aPUrv8/w640-h378/pic2.jpg" width="640" /></a></p><p>Leela was a pawn up and it chose to give a knight for a pawn, Stockfish immediately saw a win. The queens were exchanged, Leela avoided captures but Stockfish reduced to a 7-man win and mated a few moves later.</p><p>In <a href="https://tcec-chess.com/#div=sf&game=6&season=25">game 6</a> Stockfish blocked the long diagonal with pawns in the center so the black LS bishop would be less effective. Leela placed a pawn on e3 through a minor piece exchange and gave one pawn to open the king side. Stockfish hid its king behind the black pawn.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgbq22m_qGoTjwewwyqQRpBA1cqFkoYJOAB0VtVXc9dUpNlxWWfEZtRROwIVFj1Hw11PVq96lyrGwQqSxvhPheMKNssAsdkekxSpWAQhrRvBjYxzNRoKeOh8_WxV_5la25-gxIy04wGXO8bHiCq2j70YXhrVMTzJ5LZmsikVtW8FjcI17Xd-ATYYCecAxw/s1182/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="697" data-original-width="1182" height="378" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgbq22m_qGoTjwewwyqQRpBA1cqFkoYJOAB0VtVXc9dUpNlxWWfEZtRROwIVFj1Hw11PVq96lyrGwQqSxvhPheMKNssAsdkekxSpWAQhrRvBjYxzNRoKeOh8_WxV_5la25-gxIy04wGXO8bHiCq2j70YXhrVMTzJ5LZmsikVtW8FjcI17Xd-ATYYCecAxw/w640-h378/pic1.jpg" width="640" /></a></div><p>Leela attacked the long diagonal to open it, Stockfish moved its king back and captured the black d3 pawn. A series of exchanges reduced to a RBN vs RBB position and Leela centralized its bishops, the remaining rooks were exchanged on move 45.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjumdMOWEbXb-ngbsfKv2C5YXLREy5D_WbQyPq7LMobmTivFVrNlIVcRhObPR6P7lkCCjn4w3y-YKjqM1Kj3N-2NR-sVIQsxYLQytIzdrfB1DpkVG0XAnrc5YqPwNvlnylg1Hp6Gvebfrs89a2MRrBFnO5miMflRNpeQ1oWlu8zI-ZW-2qEv2XJBV7LF1g/s1168/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="693" data-original-width="1168" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjumdMOWEbXb-ngbsfKv2C5YXLREy5D_WbQyPq7LMobmTivFVrNlIVcRhObPR6P7lkCCjn4w3y-YKjqM1Kj3N-2NR-sVIQsxYLQytIzdrfB1DpkVG0XAnrc5YqPwNvlnylg1Hp6Gvebfrs89a2MRrBFnO5miMflRNpeQ1oWlu8zI-ZW-2qEv2XJBV7LF1g/w640-h380/pic2.jpg" width="640" /></a></p><p>Material was equal but the black bishop pair was very effective and all the white pawns were isolated. Leela captured a pawn and created a pawn majority on the queen side. It took a while before Leela captured another pawn and created a passer. Stockfish lost material trying to block the black pawns, Leela mated with the bishop pair. There were two black wins in this game pair, the score is 3-3.</p><p>Games 7-8 started with a 32-ply line in the Ruy Lopez, Chigorin defense, still played in high level human chess. The center and queen side were blocked except the open a file. In game 7 Leela moved a rook forward on the a file, added a second rook and tried to attack. In a long PV agreement the engines exchanges pieces, evals were stable. On move 43 the game reached a QRN vs QRN position, each engine with 7 pawns. The engines shuffled for a while, Stockfish's eval dropped after Leela moved a pawn on the king side. The engines slowly exchanged pieces and pawns, on move 95 the game reached a knight ending. Leela's eval slowly came down, the game was adjudicated on move 116. </p><p>In <a href="https://tcec-chess.com/#div=sf&game=8&season=25">game 8</a> Stockfish moved a rook forward through the open a file and placed it on c6. Leela moved a knight to attack the rook but Stockfish kept it there, and Leela did not take since the result would be a protected passer on c6. Stockish's eval started to increase and it moved pieces to the king side. On move 32 Stockfish offered a knight on the king side, Leela didn't take but its eval dropped.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh0ns0IpYDyT8ZPde4Gf5x6Cu26R_j0-6ZUov_JH47a2R4b8yyHmxnLKsxIoG2mN33Os2WS4v2kKMpOcqY06Ml0Fcwnq_XfcZY7xohejaTzDcP1VrK37F7oQlfMOJ-4XnbWL3aG8xIpzCBm5MfT79g3IssZYjaEAM0BwvrA_Ex9jmSYBP9yqtll3j5CMkc/s1179/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="691" data-original-width="1179" height="376" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh0ns0IpYDyT8ZPde4Gf5x6Cu26R_j0-6ZUov_JH47a2R4b8yyHmxnLKsxIoG2mN33Os2WS4v2kKMpOcqY06Ml0Fcwnq_XfcZY7xohejaTzDcP1VrK37F7oQlfMOJ-4XnbWL3aG8xIpzCBm5MfT79g3IssZYjaEAM0BwvrA_Ex9jmSYBP9yqtll3j5CMkc/w640-h376/pic1.jpg" width="640" /></a></div><p>For 3 consecutive moves Stockfish's move surprised Leela, Leela spent over 4 minutes per move and still its eval remained low while Stockfish's eval jumped. On move 35 Leela finally understood Stockfish's plan, its eval jumped and the PVs agreed. Both the offered white pieces were taken though material was still equal. The black king was in danger, in another series of exchanges the engines reduced to a RB vs RN position with white 2 pawns up. Leela gave another pawn to create a passer in desperation.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhlbD1mMb47ZFrZoPZWPDxO71mw_-19orLSlHwys7V7mwvZDSmamR0SpZJ4_dYZSINloJk76yN4yKsw1N30CSOjUH1FHdkcO9htOhrIGLdysKmdNiNlcO4w_4B7NvUKhMsR7dIxgIM6jFEgb_a1hLBMUSJ7tTxZ2VlHgSqDhv6blmqb9lnA3DOq326Z6ZI/s1180/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="694" data-original-width="1180" height="376" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhlbD1mMb47ZFrZoPZWPDxO71mw_-19orLSlHwys7V7mwvZDSmamR0SpZJ4_dYZSINloJk76yN4yKsw1N30CSOjUH1FHdkcO9htOhrIGLdysKmdNiNlcO4w_4B7NvUKhMsR7dIxgIM6jFEgb_a1hLBMUSJ7tTxZ2VlHgSqDhv6blmqb9lnA3DOq326Z6ZI/w640-h376/pic2.jpg" width="640" /></a></p><p>The black passer was quick but Stockfish used a back rank mate threat to capture it. Stockfish gained material, queened a passer and mated. Stockfish wins the game pair, it leads 4-3.</p><p>Games 9-10 started with a 20-ply line in the Queen's gambit accepted, Godes variation, where white regained the pawn and both queens moved forward. In game 9 there was a long PV agreement starting from move 16. The engines opened the board, exchanged pawns and a pair of rooks and evals came down slowly. Leela grabbed a pawn, Stockfish countered with a threat on the black king and evals dropped close to 0. In a series of exchanges Stockfish gave a rook and a knight for the white queen, the game was adjudicated a few moves later. In game 10 there were no exchanges after the start, Leela gave a pawn on move 24 and a few moves later the queens were exchanged. The engines slowly exchanged pieces and pawns and evals came down. In a series of exchanges the engines traded R for BB and then reduced to a BNN vs RN position. Then engines shuffled and the game ended in a 50 move draw.</p><p><br /></p>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com0tag:blogger.com,1999:blog-4430065842059358622.post-32589999490976774582023-10-15T01:02:00.000+03:002023-10-15T01:02:19.883+03:00Season 25 premier division statistics<p>A summary <a href="https://drive.google.com/open?id=1dpikbAHWxz1wLcsOzG0kxKCk0Hn67IYJPL8B1wzj_rk" target="_blank">statistics table</a> of previous stages and seasons. </p><p><b>Draw rate, wins</b></p><p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgVOCm5kKRYoChOBaHT76Su3V0s7MULERnwRcb6nuTEi2TeJsBx66bax07P6KYhiDHzyIG_xHdHICqrlwfwDoNf1tiP6VjjSehMfsjdMaHNtXpypC7UsjNcoX4R_ZsdL9fJFJzIiE6hZYBlYld5pgVBXe7fSEWstjwK5QdMar2iRA1ArfcIPDd6t4-vJdI/s480/S25.pd.g1.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgVOCm5kKRYoChOBaHT76Su3V0s7MULERnwRcb6nuTEi2TeJsBx66bax07P6KYhiDHzyIG_xHdHICqrlwfwDoNf1tiP6VjjSehMfsjdMaHNtXpypC7UsjNcoX4R_ZsdL9fJFJzIiE6hZYBlYld5pgVBXe7fSEWstjwK5QdMar2iRA1ArfcIPDd6t4-vJdI/s320/S25.pd.g1.jpg" width="320" /></a></div><b></b><p></p><p>Final draw rate was 52.7%. </p><p></p><p><b>Game termination</b><br /><br />The three most common game termination causes were:<br />42.0% - TCEC draw rule<br />28.0% - SyzygyTB<br />19.9% - Mate<br /><br />There was one crash in the stage, Leela crashed on time, a very rare event.<br /></p><p><b>Moves per game</b></p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgyDnAh_UvCiLTaUHC2mhE_nZUfkvwki2II73L8X1JCgne-goi68SFjqL-_5lkk-KVfBIT08SuyyNlzKjohQYY2wYIzqvA4251VLXFaE6bLGEDKS35-So3-1yRfrAR4eJZU3pvsbfa0YssTXnNIe-O4O6hNyCGl8StVrHErLACJvf4vBXrP8XNhkDnC0xE/s480/S25.pd.g2.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgyDnAh_UvCiLTaUHC2mhE_nZUfkvwki2II73L8X1JCgne-goi68SFjqL-_5lkk-KVfBIT08SuyyNlzKjohQYY2wYIzqvA4251VLXFaE6bLGEDKS35-So3-1yRfrAR4eJZU3pvsbfa0YssTXnNIe-O4O6hNyCGl8StVrHErLACJvf4vBXrP8XNhkDnC0xE/s320/S25.pd.g2.jpg" width="320" /></a></p><p>Median= 69.3<br />Average= 75.2<br /><br />There were 43 games longer than 100 moves, the longest was 268 moves (Ethereal - Leela, game 135, draw). <br /><br /><b>Time per game (hours)</b></p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjgx_WqsrpoeFmwY0AdqffXT-gwI8Q-o05i8GiEP89yeXGLi9YkAunlsXfe0CM4nVYJcSLaBfXq3SWE9PGBPrtKCXCrrqsQGqgra2Cp-2ncFRLp15SoiAAkgdyaTSG5tt4j6xh1ruiNJVnsd9Se_4D0fa9a_53PkiTsP2ZC7OzZyHOeN0QZslgG5yk4kaI/s480/S25.pd.g3.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjgx_WqsrpoeFmwY0AdqffXT-gwI8Q-o05i8GiEP89yeXGLi9YkAunlsXfe0CM4nVYJcSLaBfXq3SWE9PGBPrtKCXCrrqsQGqgra2Cp-2ncFRLp15SoiAAkgdyaTSG5tt4j6xh1ruiNJVnsd9Se_4D0fa9a_53PkiTsP2ZC7OzZyHOeN0QZslgG5yk4kaI/s320/S25.pd.g3.jpg" width="320" /></a></p><p>Median= 2:06<br />Average= 2:03<br /><br /><b>Openings</b><br /><br />There were variable length book openings in this stage. The first letter of the ECO codes was distributed as follows: </p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi5i6PSKCxKoJRwLTjaWzS-U2RQD5BbVOcbERHdTRUkQEtTQcb9Mh8gfaInR2eaM-gLidQreFwnTj7-3voQSOM7jfNMMr58qh7I-fb5hSIkSelZb_rM25gfR1Ghf6YbaDrS6H_xxbgkVCX1Dz1iW7qAeL4nP29-aQDRRy-RHkw9UQeiJMLrfKJ8HkzbyYU/s480/S25.pd.g4.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi5i6PSKCxKoJRwLTjaWzS-U2RQD5BbVOcbERHdTRUkQEtTQcb9Mh8gfaInR2eaM-gLidQreFwnTj7-3voQSOM7jfNMMr58qh7I-fb5hSIkSelZb_rM25gfR1Ghf6YbaDrS6H_xxbgkVCX1Dz1iW7qAeL4nP29-aQDRRy-RHkw9UQeiJMLrfKJ8HkzbyYU/s320/S25.pd.g4.jpg" width="320" /></a></p><p>The engines had almost no freedom to choose the opening variant, all of the game pairs repeated the same ECO code and the opening variant twice.<br /></p><p><b>Reverse pairs, wins</b></p><p style="text-align: left;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEikH-_oSEvPGSgP-uVkM4MORn4zSYB_Kh7JFdmFrtDTvwQwEuPjT5bLSYAmLASDWvIL5NOgZ9756A565CqqrankKiOIo7zxd09sxPN6GNlilLrSa1aTxSuuyjwHyEzPqPKAmxemhG3Qp0Z1bIc1xy6rlEsX4h5PYZlP1V9seL-BBkmybJM6-EbFxM8445I/s480/S25.pd.g5.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEikH-_oSEvPGSgP-uVkM4MORn4zSYB_Kh7JFdmFrtDTvwQwEuPjT5bLSYAmLASDWvIL5NOgZ9756A565CqqrankKiOIo7zxd09sxPN6GNlilLrSa1aTxSuuyjwHyEzPqPKAmxemhG3Qp0Z1bIc1xy6rlEsX4h5PYZlP1V9seL-BBkmybJM6-EbFxM8445I/s320/S25.pd.g5.jpg" width="320" /></a></p><p style="text-align: left;"><b><span style="font-family: arial;">Reverse pairs, same moves</span></b></p><p style="text-align: left;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgdUiwFUM-GrW-S1XIqZgiSS9SkorNqtO8XGuOhM7usBsMK_cNdbFyrSSR5ZNcvRwivsQ0k3h9T5qlVlBB6RNxiL3hMz-WRbhyphenhyphenX5ZoPf4QvElSBcktM_nsJKjv3p0IklCk3Kg_i1NtClazaJHKVfWzbOVLQ-901Tn7fRVdOZSlXMAE06j-35h9wUnKjf0k/s480/S25.pd.g6.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgdUiwFUM-GrW-S1XIqZgiSS9SkorNqtO8XGuOhM7usBsMK_cNdbFyrSSR5ZNcvRwivsQ0k3h9T5qlVlBB6RNxiL3hMz-WRbhyphenhyphenX5ZoPf4QvElSBcktM_nsJKjv3p0IklCk3Kg_i1NtClazaJHKVfWzbOVLQ-901Tn7fRVdOZSlXMAE06j-35h9wUnKjf0k/s320/S25.pd.g6.jpg" width="320" /></a></p><p style="text-align: left;">Pairs of reverse games diverged less quickly than usual, 23.8% diverged immediately out of book, 60.7% of the pairs diverged at most after 1 move. The longest repeated sequence of moves was 25 plys (Leela - Stockfish, games 306 and 334, Sicilian Velimirovic attack, two draws) </p><p style="text-align: left;"><br /></p>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com0tag:blogger.com,1999:blog-4430065842059358622.post-52605504183483269842023-10-11T01:18:00.006+03:002023-12-01T15:41:47.622+02:00Season 25 premier division final results<p><i>Back from vacation, I am going over the games but with the backlog I'm facing I will be more selective about which games I summarize. This post will cover the last 4 RRs.</i></p><p><b>Final Standings</b></p><p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhNunX8vgHvAXkKPWQxheQVyEdm-GLH8RA5sOrYDmjxO5IrzaR3xKwN_eDMA6hSlFg3m_eNHBe-O_yrKGCBf_0_nwNEfGBHV0H-xYgtmsHZX7ZZtY2GJNRfyYb2rkhGqdeO6MjPOu5bfQD8_0fat1VzoUw5LuEDOF51vZ7Ia4xTr7iJoVVgSzuXEB6uqWg/s670/tab.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="637" data-original-width="670" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhNunX8vgHvAXkKPWQxheQVyEdm-GLH8RA5sOrYDmjxO5IrzaR3xKwN_eDMA6hSlFg3m_eNHBe-O_yrKGCBf_0_nwNEfGBHV0H-xYgtmsHZX7ZZtY2GJNRfyYb2rkhGqdeO6MjPOu5bfQD8_0fat1VzoUw5LuEDOF51vZ7Ia4xTr7iJoVVgSzuXEB6uqWg/w400-h380/tab.jpg" width="400" /></a></div><div class="separator" style="clear: both; text-align: left;"><br /></div><p style="clear: both; text-align: left;">Stockfish, Leela, KomodoDragon and RubiChess advance to the playoff stage. Stockfish was dominant from the start, it won 36/42 game pairs without loss, including 3 wins against Leela and 5 against KomodoDragon. </p><p style="clear: both; text-align: left;">TBD</p><p style="clear: both; text-align: left;">Going into the playoff the standings within the top 4 engines are: Stockfish +14, Leela +3, KomodoDragon -3, RubiChess -14.</p><div><p></p><p><b>Interesting games</b></p><p><a href="https://tcec-chess.com/#div=p&game=227&season=25">game 227</a>, <span style="background-color: #04ff00;">Stockfish</span> - RubiChess: The game reached a QB vs RBB position with two pawns left on the king side for both engines. Evals were stable, RubiChess held for a long time but was inaccurate in time trouble and evals started to increase after move 57. Stockfish improved slowly, on move 77 it captured a pawn, then it pushed a passer and traded a pair of bishops. The game ended in mate on move 109.</p><p><a href="https://tcec-chess.com/#div=p&game=236&season=25">game 236</a>, <span style="background-color: #04ff00;">Leela</span> - RubiChess: The game reached a RNN vs RR position, the white knights controlled many squares and restricted the black rooks. Leela captured a pawn and created connected passers. RubiChess traded a rook for the two knights but couldn't prevent a queening. The game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=242&season=25">game 242</a>, <span style="background-color: #04ff00;">Stoofvlees</span> - Ethereal: Stoofvlees pushed pawns on the king side and castled long. Evals increased slowly and Stoofvlees opened the king side. Ethereal tried to counter on the queen side, it gave a rook for a knight and two pawns and created passers there. Stoofvlees hid its king behind a black pawn, then reduced to a RR vs RN position. Stoofvlees pinned the black knight and captured it, the gam ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=247&season=25">game 247</a>, <span style="background-color: #04ff00;">Ethereal</span> - Leela: The engines reduced to a RB vs RB position, material was equal but Ethereal had a passer on the queen side. Ethereal pushed the passer and moved its king forward as well, it used a mate threat to capture pawns and created more passers. Leela couldn't prevent a queening, game over.</p><p><a href="https://tcec-chess.com/#div=p&game=248&season=25">game 248</a>, <span style="background-color: #04ff00;">Stockfish</span> - Stoofvlees: Stockfish was a pawn up in a RB vs RN position with low evals, Stoofvlees was hopeful when it reduced to a rook ending but Stockfish's eval jumped. Stockfish had a pawn majority on the king side, it pushed these pawns forward while Stoofvlees captured two pawns on the queen side. It took Stoofvlees 9 moves to realize it was losing, it lost its rook for the white passers and the game ended in a tablebase win. </p><p><a href="https://tcec-chess.com/#div=p&game=250&season=25">game 250</a>, <span style="background-color: #04ff00;">Leela</span> - Stockfish: Stockfish gave a rook for a knight while the white king moved without castling. Evals slowly increased, Leela attacked through the opne h file and Stockfish walked its king back to the center. Leela gave the material back and the game reached a RB vs RN position. Leela created connected passers, then gave material to promote one to a queen. The game ended in a tablebase win.</p><p><i>Standings after RR9: Stockfish +28, Leela +15, KomodoDragon +8, Ethereal 0, RubiChess -3, Stoofvlees -9, Igel -16, SlowChess -23.</i></p><p><a href="https://tcec-chess.com/#div=p&game=254&season=25">game 254</a>, <span style="background-color: #04ff00;">KomodoDragon</span> - Ethereal: KomodoDragon castled long, it captured a pawn and opened the king side. Ethereal tried to counter on the queen side, as a result KomodoDragon created a passer there. Ethereal stopped the passer on the 7th rank but lost a rook for a knight. KomodoDragon reduced to a king and pawns ending two pawns up, queened two pawns and mated.</p><p><a href="https://tcec-chess.com/#div=p&game=259&season=25">game 259</a>, <span style="background-color: #04ff00;">Stockfish</span> - KomodoDragon: KomodoDragon grabbed a pawn with its queen, evals slowly increased. Stockfish used the opening to double rooks on the b file and drive the black queen back. KomodoDragon exchanged pieces and reduced to a RRB vs RRN position. Stockfish went after the isolated black pawns, it exchanged a pair of rooks and captured 3 pawns. KomodoDragon couldn't prevent a queening, the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=266&season=25">game 266</a>, <span style="background-color: #04ff00;">Leela</span> - KomodoDragon: There were almost no exchanges after the start, the engines played behind their pawn lines with stable evals. The first pawn exchange was on move 51, a few moves later Leela went a pawn up. The engines shuffled and played in blitz mode, evals increased after move 71. Leela gave back the pawn and created two passers, KomodoDragon gave a bishop in desperation. Leela queened a passer and used its material advantage to force mate.</p><p><a href="https://tcec-chess.com/#div=p&game=270&season=25">game 270</a>, <span style="background-color: #04ff00;">Ethereal</span> - Stoofvlees: A series of exchanges opened the king side, Ethereal gave a rook for a bishop and pawn and created a passer. Stoofvlees realized it was in trouble in a RBN vs RRN position, Ethereal pushed the passer to the 6th rank and traded a pair of rooks. The white king moved forward, Stoofvlees captured the passer and lost its knight. Ethereal captured all the black pawns and was 4 pawns up, the white pawns moved forward and the game ended in mate.</p><p><a href="https://tcec-chess.com/#div=p&game=272&season=25">game 272</a>, <span style="background-color: #04ff00;">KomodoDragon</span> - RubiChess: KomodoDragon pushed pawns on the king side and kept its king uncastled. RubiChess gave a knight for pawns and attacked on the queen side. RubiChess regained the material and the game reached a RB vs RN position, the white king moved forward and captured a pawn. KomodoDragon gave a rook for a knight and created an unstoppable passer, it queened and mated.</p><p><a href="https://tcec-chess.com/#div=p&game=275&season=25">game 275</a>, <span style="background-color: #04ff00;">Leela</span> - Ethereal: Leela created a passer on the h file and pushed it to the 6th rank. After queens were exchanged evals started to increase, Leela walked its king to the queen side. After some shuffling Leela opened the king side, it gave the h passer and pinned a bishop, then created a passer in the center. Ethereal captured more pawns but in a series of exchanges lost material and the game reached a RB vs B position. Leela captured black pawns and the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=278&season=25">game 278</a>, <span style="background-color: #04ff00;">Stockfish</span> - Leela: Stockfish kept its king in the center and opened the h file. It gave a rook for a knight, then sacrificed a bishop and opened the g file. Leela gave a rook back and its king ran to the center, the game reached a R vs N ending. Leela played 13 moves without thinking, its eval was stable while Stockfish saw the win already. Leela slowly increased its eval, Stockfish captured pawns and queened a passer, then mated. </p><p><i>Standings after RR10: Stockfish +30, Leela +18, KomodoDragon +10, Ethereal 0, RubiChess -3, Stoofvlees -11, Igel -17, SlowChess -27. Stockfish drew game pairs against Leela and Ethereal, Leela also drew is game pair against Ethereal. RubiChess lost to the top3 and only won two game pairs, Ethereal increased its lead to 1.5 points over RubiChess, with one DRR to go.</i></p><p><a href="https://tcec-chess.com/#div=p&game=283&season=25">game 283</a>, <span style="background-color: #04ff00;">Stockfish</span> - RubiChess: Queens were off early, Stockfish was a pawn up with a passer on the queen side. RubiChess regained the pawn and captured the passer but Stockfish created another. RubiChess captured this passer as well but lost a knight. In a RBN vs RB position the black bishop was almost trapped, Stockfish slowly improved and then exchanged rooks. Eventually the game reached a B vs pawns endgame and ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=286&season=25">game 286</a>, <span style="background-color: #04ff00;">RubiChess</span> - Stoofvlees: Evals were low until move 39. RubiChess expected a queen exchange but Stoofvlees had other ideas and RubiChess' eval jumped. Stoofvlees decided to give its queen for two rooks, it saw the problem too late. The game reached a QN vs RR position, both kings were exposed but the white pieces were better. RubiChess captured both rooks for the knight and mated.</p><p><a href="https://tcec-chess.com/#div=p&game=292&season=25">game 292</a>, <span style="background-color: #04ff00;">Leela</span> - RubiChess: Both engines waited with their castling, RubiChess castled long and Leela opened the queen side while its king stayed in the center. RubiChess hid its king behind a white passer, the engines reduced to a RBN vs RBN position. Leela was a pawn up, it pushed a passer forward supported by its king. RubiChess lost its rook, the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=307&season=25">game 307</a>, <span style="background-color: #04ff00;">RubiChess</span> - Ethereal: The engines castled in opposite directions, RubiChess pushed pawns on the king side and gave a knight to expose the black king. RubiChess regained the piece and the game reached a knight ending with white a pawn up. Ethereal's eval increased, RubiChess was not convinced at first that it had an advantage. On move 32 RubiChess thought for 23 minutes, all the time it had on the clock. Only on move 55 it felt confident in its win and evals increased. It created a passer, then on move 74 it captured a pawn and created another passer. Ethereal captured one passer but lost its remaining pawns, RubiChess queened and mated.</p><p><i>Standings after RR11: Stockfish +34, Leela +20, KomodoDragon +11, Ethereal -1, RubiChess -3, Stoofvlees -12, Igel -19, SlowChess -30. The only interesting race left is for 4th place between Ethereal and RubiChess. RubiChess beat Ethereal in their direct match, but it is still 1 point behind at the start of the last RR.</i></p><p><a href="https://tcec-chess.com/#div=p&game=310&season=25">game 310</a>, <span style="background-color: #04ff00;">KomodoDragon</span> - Ethereal: Ethereal gave a rook for a bishop, the game reached a QRR vs QRN position and evals started to increase. The engines traded pawns and a pair of rooks, KomodoDragon exposed the black king while its king was safer behind pawns. On move 70 the engines were down to 2 pawns each, KomodoDragon shuffled for a long time. On move 100 the queens were exchanged, the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=315&season=25">game 315</a>, <span style="background-color: #04ff00;">Stockfish</span> - KomodoDragon: The center was blocked, KomodoDragon walked its king to the king side. Stockfish opened the king side and exchanged all rooks, it captured a pawn and evals slowly increased. The game reached a BN vs BN position, the endgame was slow, it took Stockfish 20 moves to exchange bishops. Stockfish captured pawns and created passers, eventually it queened and mated.</p><p><a href="https://tcec-chess.com/#div=p&game=317&season=25">game 317</a>, <span style="background-color: #04ff00;">Igel</span> - Ethereal: Ethereal castled long and Igel pushed pawns on the queen side. Igel gave two pawns and created an advanced passer, it captured a pawn back and opened the queen side. Igel doubled rooks on the open b file, Ethereal lost its queen for a rook and a knight. The game reached a Q vs RB ending, Igel lost its passer but captured black pawns with its queen and created another passer. Ethereal lost its rook, 20 moves later the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=324&season=25">game 324</a>, <span style="background-color: #04ff00;">Stockfish</span> - Ethereal: Stockfish pushed pawns on the king side, Ethereal gave a knight for two pawns and kept the king side closed. The engines continued to trade pieces and the game reached an unusual BBN vs R position with black 3 pawns up. Stockfish had no pawns left but its pieces were coordinated. It captured two pawns and reduced to a 7-man win, the game was adjudicated 30 moves later.</p><p><i>Standings with 3 rounds to go: Stockfish +36, Leela +22, KomodoDragon +12, RubiChess -2, Ethereal -3, Stoofvlees -14, Igel -19, SlowChess -32. RubiChess closed the gap and is leading Ethereal by 0.5 points. Ethereal's loss to Igel was a surprise. The race for 4th place is wide open with 3 rounds to go including a direct match between Ethereal and RubiChess in the last round.</i></p><p><a href="https://tcec-chess.com/#div=p&game=326&season=25">game 326</a>, <span style="background-color: #04ff00;">Ethereal</span> - Stoofvlees: Ethereal gave a bishop early, then captured a rook and attacked the black king. Stoofvlees had to move its king, it captured a rook for a knight back but evals were already high. Ethereal captured a bishop and reduced to a QBN vs QB position. Ethereal chased the black king all the way to the first rank, eventually Ethereal forced mate.</p><p><a href="https://tcec-chess.com/#div=p&game=328&season=25">game 328</a>, <span style="background-color: #04ff00;">KomodoDragon</span> - RubiChess: RubiChess castled long and KomodoDragon pushed pawns on the queen side. RubiChess captured a pawn and used a bishop to block an open file, then gave a rook for a bishop to keep the king side closed. KomodoDragon gave back a rook for a bishop and created two passers. In a QRB vs QRB position KomodoDragon captured two more pawns and RubiChess couldn't block all the white passers. KomodoDragon queened twice and mated.</p><p><i>Two rounds to go Ethereal is leading again with RubiChess 0.5 points behind.</i></p><p><a href="https://tcec-chess.com/#div=p&game=331&season=25">game 331</a>, <span style="background-color: #04ff00;">Leela</span> - Ethereal: There were almost no exchanges after the start, Leela pushed a pawn to h6. Ethereal captured a pawn and Leela created a passer in the center, evals slowly increased. Ethereal blocked the passer on the 6th rank and tried to attack the exposed white king. Leela reduced to a RBN vs RBN position, Ethereal captured pawns and pushed a passer to the 2nd rank but there it stopped. Ethereal lost a rook, both advanced passers were captured and Ethereal was 3 pawns up. The white pieces were stronger, Leela gained more material, queened a passer and the game ended just before mate.</p><p><i>RubiChess beat SlowChess and now it is leading Ethereal by 0.5 points. </i></p><p><i>In the last round Ethereal failed to beat RubiChess with white, as a result RubiChess finished 4th and will play in the premier division playoff.</i></p><p><i><br /></i></p></div>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com0tag:blogger.com,1999:blog-4430065842059358622.post-73430412517959369482023-09-25T01:11:00.004+03:002023-09-25T23:08:44.003+03:00Season 25 premier division, after RR8<p><i>Scheduling note: I will be on vacation and will miss the final DRRs of the premier division. Based on the current results it is safe to say that Stockfish and Leela will be in the superfinal, even before the playoff is played. I haven't decided whether to try to complete the premier division entries when I come back (with a backlog of >100 games) or whether to cover the ongoing games and go back to ones I missed later... We'll see.</i></p><p><b>Standings after RR8</b></p><p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEitSiI4EAWgQND1ubs-B-3NYr0HTWnpy3kkP_mNkynjztCrGbzELaPG9RaW7Ni51SfBmrc-RrY3nRUwmYtzx1b5wGCfCNO3_jbGiovPqZWigbMr-YzaxZmS4UDBkL8-Qs90n1Ta_S2D1oujURMTj5ChYs3GHx3CK_Gm-PMaX_HVydtkUzAszdFifvToaTg/s667/tab.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="634" data-original-width="667" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEitSiI4EAWgQND1ubs-B-3NYr0HTWnpy3kkP_mNkynjztCrGbzELaPG9RaW7Ni51SfBmrc-RrY3nRUwmYtzx1b5wGCfCNO3_jbGiovPqZWigbMr-YzaxZmS4UDBkL8-Qs90n1Ta_S2D1oujURMTj5ChYs3GHx3CK_Gm-PMaX_HVydtkUzAszdFifvToaTg/w400-h380/tab.jpg" width="400" /></a></div><br />Stockfish drew as white against KomodoDragon, the first game it didn't win with bias. This was also only the 3rd game pair Stockfish didn't win after 28 played. Leela won 5 game pairs against the bottom 5, it drew against KomodoDragon and lost against Stockfish for the 3rd time. Ethereal and RubiChess both had 2 game pair wins and 2 losses, Ethereal keeps its slim lead in 4th place.<p><b>Interesting games</b></p><p><a href="https://tcec-chess.com/#div=p&game=171&season=25">game 171</a>, <span style="background-color: #04ff00;">Stockfish</span> - RubiChess: Stockfish opened the king side and RubiChess castled long. RubiChess gave a bishop for a pawn and exposed the white king, this led to a series of exchanges where the engines traded RN for Q. The engines reduced to a Q vs RN ending, evals were high but its still took a long time to convert. Stockfish had a passer and the white queen could give checks, pin pieces or threat forks. After 20 moves Stockfish created a second passer, RubiChess couldn't prevent a queening and then mate.</p><p><a href="https://tcec-chess.com/#div=p&game=174&season=25">game 174</a>, <span style="background-color: #04ff00;">RubiChess</span> - Stoofvlees: The center was blocked and there were only a few pawn exchanges after the start. Evals were stable, Stoofvlees offered a rook for a bishop but that would close a file and RubiChess refused. After move 35 evals started to increase, RubiChess opened the king side and created an advanced passer. Stoofvlees gave a knight for the passer, RubiChess captured a pawn and created connected passers in the center. Stoofvlees gave up when the white passers advanced, it gave material and was mated.</p><p><a href="https://tcec-chess.com/#div=p&game=177&season=25">game 177</a>, <span style="background-color: #04ff00;">Ethereal</span> - Igel: Ethereal castled long and gave a pawn on the king side. Ethereal slowly moved its major pieces to the king side, after the g file opened Ethereal gave another pawn and tripled its major pieces on the h file. Ethereal gave a rook for a knight and pawn and exposed the black king, Igel surrounded its king with pieces. Ethereal placed two static knights on the queen side while its queen and rook kept moving and making threats from all sides. Igel protected its king but it lost a few pawns, Ethereal created connected passers on the queen side. The passers slowly advanced supported by the white king, the game reached a N vs R ending. Igel lost the rook for a passer, Ethereal queened another and mated.</p><p><a href="https://tcec-chess.com/#div=p&game=178&season=25">game 178</a>, <span style="background-color: #04ff00;">Stockfish</span> - SlowChess: Stockfish captured a pawn early, the center was blocked and the engines formed long pawn lines without exchanges. Evals increased while the engines shuffled and the white king walked to the queen side. On move 48 Stockfish started to open the king side, it gave back the pawn and exposed the black king. After exchanging queens Stockfish captured a pawn and reduced to a RBN vs RBN position. Stockfish captured a second pawn and pushed connected passers forward, it gave a rook to promote to a queen and mate followed.</p><p><a href="https://tcec-chess.com/#div=p&game=180&season=25">game 180</a>, <span style="background-color: #04ff00;">Leela</span> - RubiChess: Leela moved its king to the king side without castling. All pieces were on the king side, Leela's eval jumped after RubiChess opened the f file. RubiChess gave a rook to get rid of a forward knight, Leela continued to exchange pieces until reaching a R vs N ending. Both engines pushed passers, RubiChess lost its knight, both engines queened but Leela was first and forced mate.</p><p><a href="https://tcec-chess.com/#div=p&game=182&season=25">game 182</a>, <span style="background-color: #04ff00;">KomodoDragon</span> - Leela: KomodoDragon castled long while Leela kept its king in the center. KomodoDragon captured an early pawn, the engines exchanged many pieces and pawns and Leela regained the pawn. The game reached a RN vs RB position, KomodoDragon kept the black king away and captured a pawn, reducing to a rook ending. The game continued for more than 25 moves, first KomodoDragon captured another pawn, then with 3 passers the engines reduced to a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=185&season=25">game 185</a>, <span style="background-color: #04ff00;">Stockfish</span> - Igel: Stockfish created a central passer with pawn exchanges, Igel captured a pawn but couldn't get rid of the white passer. Stockfish protected its passer with many pieces, after some preparations there was a series of exchanges that reduced to a RB vs RB position. Stockfish went two pawns up and pushed more passers forward. Igel lost its rook and the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=187&season=25">game 187</a>, <span style="background-color: #04ff00;">Leela</span> - SlowChess: Evals were low until move 22, Leela thought SlowChess blundered on move 25. In a series of exchanges the engines reduced to a RB vs RN position, SlowChess was a pawn up but its pawns were vulnerable. Leela pushed a passer forward and SlowChess lost its knight for it. Leela captured pawns and pushed more passers forward, the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=188&season=25">game 188</a>, <span style="background-color: #04ff00;">RubiChess</span> - KomodoDragon: Queens were off early, RubiChess went a pawn up and in an unusual sequence of exchanges the engines reduced to a RBN vs RNN position. After trading a bishop for a knight RubiChess created a passer. KomodoDragon lost more pawns trying to stop the passer, it gave up its pieces and the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=192&season=25">game 192</a>, <span style="background-color: #04ff00;">Stockfish</span> - Stoofvlees: Stockfish gave a rook for a knight early and opened the king side. Evals were mostly stable, Stoofvlees exchanged pieces and protected its king. The game reached a QRB vs QRB position when Stockfish's eval jumped. Stockfish attacked the black king and captured a pawn, then reduced to a queen ending. Stockfish saw the win though it took more than 20 moves to reach a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=196&season=25">game 196</a>, <span style="background-color: #04ff00;">KomodoDragon</span> - SlowChess: There were no exchanges after the start but evals started to increase. On move 22 SlowChess opened the center and gave a knight for two pawns. The engines continued to exchange pieces and the game reached a QB vs Q position. KomodoDragon used checks to capture pawns, then exchanged queens. KomodoDragon didn't try to finish the game quickly, it took almost 40 more moves to get a tablebase win.</p><p><i>Standings after RR7: Stockfish +23, Leela +10, KomodoDragon +6, Ethereal 0, RubiChess -2, Stoofvlees -7, Igel -11, SlowChess -19. Stockfish and Leela continued to win as usual, except for Leela's loss to KomodoDragon. KomodoDragon also lost to RubiChess. Ethereal held a draw as black against RubiChess, it is still in 4th place.</i></p><p><a href="https://tcec-chess.com/#div=p&game=200&season=25">game 200</a>, <span style="background-color: #04ff00;">Leela</span> - Stoofvlees: Leela castled long and forced the black king to move without castling. Stoofvlees gave two pawns and opened the queen side, Leela gave a rook for a knight and exchanged pieces to keep its king safe. Leela was two pawns up, it pushed a passer to the 7th rank. Stoofvlees gave a bishop and captured the passer, Leela attacked the black king. Stoofvlees lost material and was mated.</p><p><a href="https://tcec-chess.com/#div=p&game=201&season=25">game 201</a>, <span style="background-color: #04ff00;">Leela</span> - Igel: All pieces were on the board until move 27 when Igel gave a rook for a knight. Igel pushed pawns on the king side and tried to attack the white king, Leela exchanged pieces and reduced to a RB vs RB position. Leela was a pawn up, both engines had passers but the white ones were faster. Leela queened a passer and mated.</p><p><a href="https://tcec-chess.com/#div=p&game=202&season=25">game 202</a>, <span style="background-color: #04ff00;">Stoofvlees</span> - RubiChess: There were no exchanges after the start, the engines blocked the center and queen side. On move 45 Stoofvlees opened the king side and RubiChess captured a pawn. RubiChess gave a rook for a knight and walked its king to the queen side. The engines exchanged minor pieces and opened files on the king side, then there was a long period of shuffling. On move 97 Stoofvlees moved its queen forward followed by a rook. After a while the engines exchanged queens and reduced to a RRB vs RBN position. Stoofvlees trapped and captured the black bishop, RubiChess gave two pawns in desperation and created a passer. Stoofvlees queened and mated. There were two white wins in this game pair. </p><p><a href="https://tcec-chess.com/#div=p&game=204&season=25">game 204</a>, <span style="background-color: #04ff00;">Ethereal</span> - SlowChess: There were no exchanges after the start, the center and queen side were blocked. Ethereal castled long and slowly prepared an attack on the king side. Evals slowly increased, there was one minor piece exchange and Ethereal pushed pawns on the king side. On move 58 Ethereal gave a knight for two pawns and exposed the black king. SlowChess tried to counter on the queen side but Ethereal hid its king behind a black pawn. SlowChess gave back a knight and surrounded its king with pieces, but it lost material and was mated.</p><p><a href="https://tcec-chess.com/#div=p&game=205&season=25">game 205</a>, <span style="background-color: #04ff00;">Igel</span> - Ethereal: Igel castled long, then gave a pawn and opened the king side. After exchanging a pair of rooks Igel regained the pawn on the queen side and created a passer. Ethereal had a passer on the king side, the engines shuffled for a while, then reduced to a NN vs BN position. The black bishop was blocked by its own pawns, Ethereal gave it and captured a pawn. Igel used one knight to block the black passer, the other knight captured pawns until there were none left. The game ended in a tablebase win. There were two white wins in this game pair. </p><p><a href="https://tcec-chess.com/#div=p&game=209&season=25">game 209</a>, <span style="background-color: #04ff00;">RubiChess</span> - Igel: There were many early exchanges, the game reached a QRN vs QRN position with white a pawn up. After exchanging rooks RubiChess managed to capture a second pawn and created a passer. RubiChess pushed the passer forward and Igel lost the knight for it. The game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=210&season=25">game 210</a>, <span style="background-color: #04ff00;">Leela</span> - KomodoDragon: Leela castled long and KomodoDragon tried to open the queen side. Leela went a pawn up and exchanged pieces to keep its king safe. The game reached a RB vs RB position, both engines had a passer a square away from promotion. KomodoDragon had to abandon its passer, Leela pushed a second passer forward and forced a queening and mate. There were two white wins in this game pair. </p><p><a href="https://tcec-chess.com/#div=p&game=211&season=25">game 211</a>, <span style="background-color: #04ff00;">Stoofvlees</span> - SlowChess: The engines castled in opposite directions and both pushed pawns facing the opponent's king. Evals started to increase when Stoofvlees gave a knight for two pawns and opened the king side. SlowChess gave a bishop back to let its queen move forward, then queens were exchanged. Stoofvlees doubled rooks on the g file, then captured pawns until it was a pawn up with passers on both sides. The engines reduced to an opposite color bishops ending, Stoofvlees captured two more pawns and that was enough for a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=212&season=25">game 212</a>, <span style="background-color: #04ff00;">Stockfish</span> - Ethereal: The engines castled in opposite directions, there were many early exchanges and Stockfish managed to place a pawn on f6. The game reached a double rook ending with white a pawn up, the black king was restricted on the king side. Ethereal managed to capture the f6 pawn and then exchanged a pair of rooks. Both engines had 3 passers, the white ones were connected. That was enough for Stockfish to queen a passer first and force mate.</p><p><a href="https://tcec-chess.com/#div=p&game=214&season=25">game 214</a>, <span style="background-color: #04ff00;">Ethereal</span> - Stoofvlees: Stoofvlees gave a pawn early and opened the queen side. The white king was stuck in the center, Stoofvlees gave a knight for a pawn and opened the d file where it doubled queen and a rook. Ethereal was not intimidated, it kept its king safe even when the second black rook moved forward. Ethereal moved its rooks to the 7th rank and attacked the black king. Stoofvlees tried to exchange pieces but it was soon mated.</p><p><a href="https://tcec-chess.com/#div=p&game=216&season=25">game 216</a>, <span style="background-color: #04ff00;">KomodoDragon</span> - RubiChess: Evals were stable for a long time, with only a few exchanges. After move 35 KomodoDragon's eval started to increase, it half opened the g file and put all its major pieces there to threaten the black king. RubiChess lost a knight, after a while the engines reduced to a RB vs R position. RubiChess was two pawns up with connected passers, KomodoDragon pushed a passer forward and the black rook had to block it. The white king captured the black passers, KomodoDragon queened and the game ended in a tablebase win. There were two white wins in this game pair. </p><p><a href="https://tcec-chess.com/#div=p&game=217&season=25">game 217</a>, <span style="background-color: #04ff00;">KomodoDragon</span> - Igel: KomodoDragon gave a pawn early, after Igel castled KomodoDragon attacked the king side and exchanged DS bishops. Igel's king side was weak on the dark squares, KomodoDragon regained the pawn and attacked with its major pieces. The game reached a QRB vs QRB position with a white passer on the 7th rank. KomodoDragon captured two pawns and after a while reduced to a same colored bishops ending. A combination of a light squared bishop and pawns on dark squares kept the black king away, KomodoDragon queened a passer and mated.</p><p><a href="https://tcec-chess.com/#div=p&game=218&season=25">game 218</a>, <span style="background-color: #04ff00;">RubiChess</span> - SlowChess: The center and queen side were blocked, the engines shuffled and SlowChess walked its king to the queen side. RubiChess' eval started to increase on move 30, in a series of exchanges SlowChess gave a bishop for two pawns and the king side opened. The game reached a RRB vs RR position, RubiChess captured pawns and exchanged a pair of rooks, then it captured the last black pawn and the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=219&season=25">game 219</a>, <span style="background-color: #04ff00;">Leela</span> - Ethereal: Leela's eval jumped after Ethereal grabbed a pawn on the queen side, Leela opened the h file and threatened the black king. Ethereal placed all its major pieces on the b file as a counter attack, Leela castled its king and kept it safe. Leela gave a second pawn and opened a file in the center, the threat to the black king forced Ethereal to give its queen and the game reached a QRN vs RRB position. Ethereal tried to move its king away, Leela pushed a passer forward. Leela gave a rook and queened, then gave away the material and reduced to a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=222&season=25">game 222</a>, <span style="background-color: #04ff00;">Stockfish</span> - Leela: see featured game below.</p><p><b>Featured game: Stockfish - Leela</b><br /><a href="https://tcec-chess.com/#div=p&game=222&season=25">game 222</a></p><p>After the start the engines opened the b file, Stockfish thought that Leela castled its king too soon. Then Leela half opened the f file and gave a rook for a knight, Stockfish's eval jumped yet Leela's eval was still stable. Stockfish surprised Leela on move 21, after two moves without thinking Leela spent 4 minutes to consider its reply and its eval also jumped. </p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEirNJ3Dac9ATBidNrq0J-LJuvZ07y6OCveRgTUr-7O0oG6TfpbVPgsXSnHlYsYR6eSqslZ16BTNM42uLLOrwdReVeOWhWljNAhHfqvI71KvC3AJ11SjBtiPspvZn1Kp_s6_YDk4rJysaD6942yYfzloiJOvBI1O4MvxaevB6_eRtdIKa_GmQ6lP-edPuu0/s1191/pic1.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="697" data-original-width="1191" height="374" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEirNJ3Dac9ATBidNrq0J-LJuvZ07y6OCveRgTUr-7O0oG6TfpbVPgsXSnHlYsYR6eSqslZ16BTNM42uLLOrwdReVeOWhWljNAhHfqvI71KvC3AJ11SjBtiPspvZn1Kp_s6_YDk4rJysaD6942yYfzloiJOvBI1O4MvxaevB6_eRtdIKa_GmQ6lP-edPuu0/w640-h374/pic1.jpg" width="640" /></a></div><br /><div class="separator" style="clear: both; text-align: left;">The engines played out a long PV agreement, most pieces were exchanged and the game reached a QRN vs QR position on move 31. Leela was two pawns up but with such high evals it was clear both engines knew Stockfish was winning.</div><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj8-wKX5pPLL5oIXHy9iZ17VM2tMv2KD5QI2UT8mLSh4GuY8SwEnM5F80N2cZzp---S6WwkVaOa90oiLlk-y0hsotaL4Wbn13gq-_PdsDx8cOhBfXq8qeHS4Gtfe_RGQnipcqltS3RX8NlaHDZNCR_fFplj1zedu8jBT4MFfo58J7I_NqeFJ7xfmYMMe-k/s1186/pic2.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="697" data-original-width="1186" height="376" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj8-wKX5pPLL5oIXHy9iZ17VM2tMv2KD5QI2UT8mLSh4GuY8SwEnM5F80N2cZzp---S6WwkVaOa90oiLlk-y0hsotaL4Wbn13gq-_PdsDx8cOhBfXq8qeHS4Gtfe_RGQnipcqltS3RX8NlaHDZNCR_fFplj1zedu8jBT4MFfo58J7I_NqeFJ7xfmYMMe-k/w640-h376/pic2.jpg" width="640" /></a></p><p>The white king only had a knight as cover but Leela could not attack it. Stockfish quickly captured a pawn and created a passer. After exchanging rooks Stockfish attacked the black king and captured two more pawns. The white passers advanced and Leela lost its queen, the game ended in a tablebase win.</p><p><br /></p>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com0tag:blogger.com,1999:blog-4430065842059358622.post-47279013254500226602023-09-19T01:36:00.007+03:002023-09-22T01:42:22.557+03:00Season 25 premier division, after RR6<p><b>Standings after RR6</b></p><p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg_SKTzLhQqOkrj4L-5XH0XrRVw7wQfnK6XBnk05dukf0SayjAEMPDlfpp9MXnXyvAw71OUdibSzL1_HAzRHI9_sg5bj7bnxgpI-VpDbZitZ7ccvPCFqPUZCgYIynum5NMRuLukwRDyYuAGC_qowQTYQZupcwPHY6tF366X9xVH1WLb-QcjPhVvLUbuczA/s700/tab.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="630" data-original-width="700" height="360" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg_SKTzLhQqOkrj4L-5XH0XrRVw7wQfnK6XBnk05dukf0SayjAEMPDlfpp9MXnXyvAw71OUdibSzL1_HAzRHI9_sg5bj7bnxgpI-VpDbZitZ7ccvPCFqPUZCgYIynum5NMRuLukwRDyYuAGC_qowQTYQZupcwPHY6tF366X9xVH1WLb-QcjPhVvLUbuczA/w400-h360/tab.jpg" width="400" /></a></div><br />Stockfish is still perfect with bias (usually as white, one game as black), it lost a game against Stoofvlees but drew the game pair. Leela had 4 game pair wins against the bottom5, it drew the game pair against KomodoDragon. KomodoDragon won 3 game pairs against the bottom5, its 3rd place is secure. Both Ethereal and RubiChess lost two game pairs against the top3, Ethereal won two game pairs while RubiChess won only one and lost one. As a result Ethereal is in 4th place 0.5 points ahead of RubiChess.<p><b>Interesting games</b></p><p><a href="https://tcec-chess.com/#div=p&game=114&season=25">game 114</a>, <span style="background-color: #04ff00;">Ethereal</span> - KomodoDragon: KomodoDragon was up a pawn but Ethereal developed its pieces faster. Ethereal gave a knight and attacked the black king, KomodoDragon exchanged queens and gave the piece back. Ethereal had an advanced passer and KomodoDragon gave a knight to stop it, the game reached a RBN vs RN position. The engines cleared the king side pawns, KomodoDragon tried to keep its pieces safe, Ethereal hunted the black king and mated.</p><p><a href="https://tcec-chess.com/#div=p&game=121&season=25">game 121</a>, <span style="background-color: #04ff00;">Ethereal</span> - Igel: Ethereal castled long and pushed pawns on the king side. Igel exchanged minor pieces and the game reached a QRR vs QRR position, Ethereal gave a pawn and opened files on the king side. Both the black king and queen became targets, Igel tried to exchange pieces but Ethereal managed to avoid this. Ethereal forced a rook for queen exchange, then Igel lost more material an dthe game ended just before mate.</p><p><a href="https://tcec-chess.com/#div=p&game=122&season=25">game 122</a>, <span style="background-color: #04ff00;">Stockfish</span> - SlowChess: There were many early exchanges that opened the center, material was equal but evals kept increasing. The game reached a RBN vs RBN position, SlowChess had two isolated pawns on the queen side and Stockfish captured both after a while. SlowChess gave a knight for a passer, it left another passer alone, I'm not sure why. SlowChess lost the bishop for the passer, Stockfish gained more material and mated.</p><p><a href="https://tcec-chess.com/#div=p&game=125&season=25">game 125</a>, <span style="background-color: #04ff00;">Igel</span> - RubiChess: There were no exchanges after the start, the engines formed long pawn lines in the center and king side. Igel's eval jumped after RubiChess opened the a file and Igel went a pawn up. All rooks were exchanged, then Igel closed the hole in its pawn wall with a bishop. RubiChess could only wait as Igel prepared its pieces. When it was ready Igel moved the bishop and a series of exchanges reduced to a BN vs BN position. The white king moved forward, after exchanging bishops Igel captured 3 more pawns. Igel queened a passer and mated.</p><p><a href="https://tcec-chess.com/#div=p&game=129&season=25">game 129</a>, <span style="background-color: #04ff00;">Stockfish</span> - Igel: Igel captured a pawn and the engines opened the queen side, Igel preferred to keep its king in the center. Stockfish opened files on the queen side and regained the pawn. It attacked the black king, then exchanged queens and captured two pawns. The game reached a double rook ending, Stockfish pushed two passers forward. Igel captured one and lost a rook for the other, game over.</p><p><a href="https://tcec-chess.com/#div=p&game=130&season=25">game 130</a>, <span style="background-color: #04ff00;">Stoofvlees</span> - Ethereal: The black king moved without castling and the king side rook couldn't develop. The engines opened the queen side and both engines created a passer there. Stoofvlees opened the king side and its major pieces threatened f7 and the black king. Ethereal gave the f pawn, Stoofvlees created two more passers and then captured the black passer. The engines reduced to a RB vs RB position, Ethereal stopped the white passers but lost material, the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=131&season=25">game 131</a>, <span style="background-color: #04ff00;">Leela</span> - SlowChess: Leela was up a paws early, the engines reduced to a QRB vs QRN position. SlowChess regained the pawn but evals kept increasing. SlowChess couldn't defend against all threats and Leela captured a pawn, then created connected passers. Leela captured another pawn and exchanged queens, SlowChess captured a passer but lost its knight. The game ended in a tablebase win. </p><p><a href="https://tcec-chess.com/#div=p&game=136&season=25">game 136</a>, <span style="background-color: #04ff00;">Stockfish</span> - Stoofvlees: Stoofvlees gave a knight and attacked the white king, Stockfish gave material back to let its king escape to the center, leading to a BN vs R imbalance. The black queen moved forward and Stoofvlees pushed a passer, Stockfish gave 3 pawns and its queen moved forward to counter attack. Stockfish ignored the black passers and moved a rook to the back rank. It traded RB for Q and then chased the black king and mated.</p><p><a href="https://tcec-chess.com/#div=p&game=137&season=25">game 137</a>, <span style="background-color: #04ff00;">Stoofvlees</span> - Igel: Most minor pieces were exchanged early, the game reached a RRB vs RRN position. Stoofvlees had a passer on the queen side, Igel exchanged a pair of rooks and captured the passer but Stoofvlees created another. Stoofvlees captured a pawn and added a second passer, the white king moved forward and Igel couldn't prevent a queening. The game ended in a tablebase win.</p><p><i>Standings after RR5: Stockfish +16, Leela +7, KomodoDragon +2, Ethereal 0, RubiChess -1, Stoofvlees -3, Igel -8, SlowChess -13. Stockfish continues to be perfect with bias, it drew against RubiChess in white but in a black biased opening. Leela drew against RubiChess while KomodoDragon drew against SlowChess and lost against Ethereal. RubiChess had a weak RR with no wins and one loss, Ethereal is back in 4th place.</i></p><p><a href="https://tcec-chess.com/#div=p&game=142&season=25">game 142</a>, <span style="background-color: #04ff00;">KomodoDragon</span> - Ethereal: Ethereal was a pawn up while KomodoDragon had a development advantage. KomodoDragon castled long, most minors were exchanged and the game reached a QRN vs QRN position. KomodoDragon captured two pawns on the queen side and Ethereal finally castled its king. KomodoDragon slowly pushed passers forward keeping its king safe. Ethereal started to lose material and the game ended in a tablebase win. There were two white wins in this game pair.</p><p><a href="https://tcec-chess.com/#div=p&game=143&season=25">game 143</a>, RubiChess - <span style="background-color: #04ff00;">Stockfish</span>: Stockfish was a pawn up, (negative) evals started to increase after move 20. The game reached a RBN vs RBB position, RubiChess gave another pawn to weaken the black pawn structure, creating black doubled passers on the queen side. RubiChess captured 2 black pawns, then traded its rook for the black bishop pair. Ethereal a passer on both sides of the board, RubiChess captured one but lost its bishop. Stockfish queened the second passer and mated.</p><p><a href="https://tcec-chess.com/#div=p&game=144&season=25">game 144</a>, <span style="background-color: #04ff00;">Leela</span> - Stoofvlees: Evals were stable and slightly drifting down until move 30. The engines exchanged queens, the white bishop pair was very effective in the open board. Leela captured a pawn and reduced to a RBB vs RBN position, then it traded a pair of bishops and captured the last remaining black pawn. Stoofvlees couldn't stop the white passers, it lost material and the game ended in a tablebase win. </p><p><a href="https://tcec-chess.com/#div=p&game=145&season=25">game 145</a>, <span style="background-color: #04ff00;">Leela</span> - Igel: Leela castled long and opened the g file, Igel surrounded its king with pieces. Evals were drawish until move 32, the engines exchanged all rooks and evals started to increase. The game reached a QBN vs QBN position, Leela had a pawn majority on the queen side and the black pieces were far. Leela gave its two minor pieces and queened, after exchanging a pair of queens the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=147&season=25">game 147</a>, <span style="background-color: #04ff00;">Stockfish</span> - KomodoDragon: The center was blocked, Stockfish pushed pawns on the king side and placed one on h6, trapping a black bishop in the corner. Stockfish castled short, There was a lot of shuffling on the queen side but evals increased very slowly. On move 41 the engines exchanged a pair of rooks, the first piece exchange of the game. For a long time Stockfish threatened the black b5 pawn while KomodoDragon defended it. On move 78 KomodoDragon decided to give its trapped bishop for a pawn, 10 moves later Stockfish finally captured the b5 pawn and created a passer. KomodoDragon blocked the passer but Stockfish captured more pawns. KomodoDragon lost more material, Stockfish queened and mated.</p><p><a href="https://tcec-chess.com/#div=p&game=148&season=25">game 148</a>, <span style="background-color: #04ff00;">Ethereal</span> - SlowChess: Ethereal pushed a pawn to h6 and trapped a black bishop. After a while Ethereal went a pawn up, then SlowChess gave another pawn and Ethereal had a passer. SlowChess exchanged its corner bishop and all rooks, it captured the h6 pawn but couldn't stop the white passer. Ethereal gave its queen for a knight and queened the passer, in a QBB vs QN position SlowChess lost more material, Ethereal queened again and mated.</p><p><a href="https://tcec-chess.com/#div=p&game=151&season=25">game 151</a>, <span style="background-color: #04ff00;">KomodoDragon</span> - Stoofvlees: Both engines castled long, exchanges opened the center. After a series of exchanges the game reached a rook ending with white a pawn up. Stoofvlees had 3 isolated pawns, eventually KomodoDragon captured one and reduced to a tablebase win. </p><p><a href="https://tcec-chess.com/#div=p&game=155&season=25">game 155</a>, <span style="background-color: #04ff00;">Stoofvlees</span> - SlowChess: Stoofvlees moved its queen forward on the king side, SlowChess gave a pawn to open the h file and castled long. SlowChess traded queens and gave a rook for a bishop, the game reached a RR vs RB position. Both engines still had 6 pawns and the rooks were limited, for a while the engines shuffled. On move 53 Stoofvlees managed to exchange a pair of pawns and open files, one rook moved to the back rank. Stoofvlees went a pawn up and created a passer, then reduced to a winning rook ending.</p><p><a href="https://tcec-chess.com/#div=p&game=156&season=25">game 156</a>, <span style="background-color: #04ff00;">Stockfish</span> - Ethereal: The g file was half open, Stockfish placed a rook there and castled long. There were no exchanges for a while and evals slowly increased, on move 40 Stockfish started to open the board. After a series of exchanges the game reached a B vs N ending with white two pawns up and a passer on the 7th rank. The white king moved forward, Ethereal captured one passer but couldn't block two more, Stockfish queened and mated.</p><p><a href="https://tcec-chess.com/#div=p&game=158&season=25">game 158</a>, <span style="background-color: #04ff00;">Ethereal</span> - Stoofvlees: There were many early exchanges and the game reached a RBN vs RBN position with black a pawn up. Evals were stable and drifted down, Ethereal moved its rook forward and regained the pawn. Stoofvlees created a passer and pushed it forward when Ethereal's eval jumped. Stofvlees moved instantly 3 times, when it stopped to think its eval jumped as well. Ethereal prepared a beautiful trap for the black rook, after exchanging rooks it captured the isolated black pawns. After capturing the black passer Ethereal pushed its own passers forward, it queened and mated. There were two white wins in this game pair. </p><p><a href="https://tcec-chess.com/#div=p&game=160&season=25">game 160</a>, <span style="background-color: #04ff00;">KomodoDragon</span> - RubiChess: There were only a few exchanges after the start and the engines shuffled for a long time. On move 81 KomodoDragon started to open the king side and evals increased. RubiChess captured a pawn and created a passer on the queen side but its king was in danger. KomodoDragon captured two pawns and created passers, then captured the black passer and reduced to a QRB vs QRB position. RubiChess lost material for white passers, then because of a mate threat and finally KomodoDragon mated.</p><p><a href="https://tcec-chess.com/#div=p&game=161&season=25">game 161</a>, <span style="background-color: #04ff00;">KomodoDragon</span> - Igel: There were only a few exchanges after the start, evals increased very slowly. On move 35 evals jumped, in a series of exchanges KomodoDragon opened the king side and attacked with its major pieces. The game reached a QRR vs QRR position and KomodoDragon captured two pawns, then reduced to a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=162&season=25">game 162</a>, <span style="background-color: #04ff00;">RubiChess</span> - SlowChess: The center was blocked and there were only a few exchanges after the start. The first pawns were exchanged on move 23. RubiChess managed to created an advanced passer in the center and then captured a pawn. The engines exchanged pieces and reduced to a rook ending. RubiChess connected a second passer in the center, SlowChess lost its rook and the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=163&season=25">game 163</a>, <span style="background-color: #04ff00;">Leela</span> - Ethereal: There were only a few exchanges after the start, Ethereal doubled rook and queen on the half open g file and threatened the white king. Leela's eval jumped when it gave a bishop and trapped the black queen. Ethereal exchanged queens and lost a rook. The game reached a RR vs RN position, Leela had a passer on the king side and Ethereal created a passer on the queen side. Leela managed to stop the black passer on the 2nd rank, it used a mate threat to capture the black knight. The game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=164&season=25">game 164</a>, <span style="background-color: #04ff00;">Stoofvlees</span> - Stockfish: Stoofvlees opened the king side and captured a pawn. Stockfish exchanged queens and a pair of rooks, both kings were safe. The attention moved to the queen side, the engines cleared the pawns there. Stoofvlees captured another pawn and created a passer in the center. The game reached a RBN vs RBN position, the black king moved forward to block the king side. After exchanging bishops Stoofvlees trapped the black king on the h file and pushed passers in the center. Stockfish couldn't prevent a queening, the game ended in a tablebase win. There were two white wins in this game pair. </p><p><a href="https://tcec-chess.com/#div=p&game=165&season=25">game 165</a>, <span style="background-color: #04ff00;">Igel</span> - Stoofvlees: The engines exchanged minor pieces and the game reached a QRR vs QRR position. Igel went a pawn up, Stoofvlees captured two pawns back and the engines reduced to a rook ending. Despite being a pawn down the white passers were faster and Igel kept the black king away from them. Stoofvlees captured another pawn and pushed a passer to the 2nd rank, but it was not enough. Igel queened first and mated the exposed black king. There were two white wins in this game pair.</p><p><a href="https://tcec-chess.com/#div=p&game=166&season=25">game 166</a>, <span style="background-color: #04ff00;">Stockfish</span> - Leela: see featured game below.</p><p><b>Featured game: Stockfish - Leela</b><br /><a href="https://tcec-chess.com/#div=p&game=166&season=25">game 166</a></p><p>The black queen was out early, Leela avoided a queen exchange. Stockfish castled long, then used a knight to fork the black queen and capture a pawn. Leela tried to compensate by opening the long diagonal as a threat to the white king.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgx4a1jMwdnGBv2_J9LEmiKrB0k5Mf8ce_S-uGVc70oq2o_hF-SgNDHaOcR54qfCGnaQ3eS9H_SgNeT14kUv0bDQ9j08GTT24BFMfZ3caT3ShhdCxX_wP3sLpn8_2mpjgZ4XpIxmcFkU3eygI23tvGICob3p1x4omvS7BCi3d9zwdKBBIP1M3w-__bVy78/s1174/pic1.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="694" data-original-width="1174" height="378" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgx4a1jMwdnGBv2_J9LEmiKrB0k5Mf8ce_S-uGVc70oq2o_hF-SgNDHaOcR54qfCGnaQ3eS9H_SgNeT14kUv0bDQ9j08GTT24BFMfZ3caT3ShhdCxX_wP3sLpn8_2mpjgZ4XpIxmcFkU3eygI23tvGICob3p1x4omvS7BCi3d9zwdKBBIP1M3w-__bVy78/w640-h378/pic1.jpg" width="640" /></a></div><p style="clear: both; text-align: left;">Evals slowly increased though the engines shuffled for a few moves. Then the engines played out a long PV agreement, Stockfish gave a rook for a bishop, the engines continued to exchange pieces until reaching a rook ending with white still a pawn up.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEivQCORKqphEXKz0OcJ-gwuCTJ4knI0qtfJT-WfhLOPGp0cS-i9hUTlE66ddRhC37E1jzUMFJm-KSmfMSGmRH1g9K_LGojOfc1d-agDweZEZE0u1OygqLUrdVZu-nkI0IhFDB8ctu-0ERY6CItHwfgeYIMkwlBFiNoyOFvm1D1gvpMiBpurUZI9c5FDQpA/s1182/pic2.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="693" data-original-width="1182" height="376" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEivQCORKqphEXKz0OcJ-gwuCTJ4knI0qtfJT-WfhLOPGp0cS-i9hUTlE66ddRhC37E1jzUMFJm-KSmfMSGmRH1g9K_LGojOfc1d-agDweZEZE0u1OygqLUrdVZu-nkI0IhFDB8ctu-0ERY6CItHwfgeYIMkwlBFiNoyOFvm1D1gvpMiBpurUZI9c5FDQpA/w640-h376/pic2.jpg" width="640" /></a></p><p>The white king moved forward to the center. After a while Stockfish exchanged pawns on the king side and created a passer. The white king captured the black pawns on the queen side, mate was in the PV when the game ended in a tablebase win.</p><p><br /></p>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com0tag:blogger.com,1999:blog-4430065842059358622.post-57410180383959699832023-09-15T01:26:00.008+03:002023-09-17T00:19:38.196+03:00Season 25 premier division, after RR4<p><b>Standings after RR4</b></p><p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh2WD9OGctFN7peDHHCN8Z3jchMjXHwuvnawmt3IuSobQowPfw-d_MP6i9kU-FVV_EWRn6UmD1UsJT85xKyjBps_3hi-0LMaIpP3TMlMPilx2qUzaArruNc2yKJ4VEBTPW4GU0v-XAeIhbqlo8bygVP_sEdCFLGH_I3E17ZNIyITkX7IHgGix0ILcMD3nw/s661/tab.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="640" data-original-width="661" height="388" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh2WD9OGctFN7peDHHCN8Z3jchMjXHwuvnawmt3IuSobQowPfw-d_MP6i9kU-FVV_EWRn6UmD1UsJT85xKyjBps_3hi-0LMaIpP3TMlMPilx2qUzaArruNc2yKJ4VEBTPW4GU0v-XAeIhbqlo8bygVP_sEdCFLGH_I3E17ZNIyITkX7IHgGix0ILcMD3nw/w400-h388/tab.jpg" width="400" /></a></div><br /><div class="separator" style="clear: both; text-align: left;">Stockfish continues to dominate the premier division. It lost a game against Leela and won the reverse game, but it had 6 game pair wins against the other engines. Leela in 2nd place had a weak DRR with 3 game pair draws against lower ranked engines, including an unusual loss on time against SlowChess. KomodoDragon had a slightly better second DRR with 3 game pair wins, it is more secure in 3rd place. The closest race is between Ethereal and RubiChess for 4th place.</div><p></p><p><b>Interesting games</b></p><p><a href="https://tcec-chess.com/#div=p&game=59&season=25">game 59</a>, <span style="background-color: #04ff00;">Stockfish</span> - RubiChess: There were no exchanges after the start until queens were exchanged on move 23, followed by the first pawn exchange. The engines mostly shuffled though evals gradually increased, Stockfish had a space advantage and a bishop pair. On move 48 Stockfish opened the king side, RubiChess gave a rook for a bishop and reduced to a RBN vs BNN position. Stockfish created an advanced passer, RubiChess lost a knight for it. RubiChess lost more material and was mated.</p><p><a href="https://tcec-chess.com/#div=p&game=62&season=25">game 62</a>, <span style="background-color: #04ff00;">RubiChess</span> - Stoofvlees: Both engines castled long, there was some shuffling after the start and then Rubihess gave a knight for two pawns and exposed the black king. Stoofvlees surrounded its king by pieces, it missed something in a complicated position full of threats and pins and evals started to jump. In a eries of exchanges RubiChess gave a rook for a knight, the black king had less protection. This allowed RubiChess to reduce to a QB vs RR ending two pawns up. Stoofvlees couldn't protect its king, it lost pieces and was mated.</p><p><a href="https://tcec-chess.com/#div=p&game=66&season=25">game 66</a>, <span style="background-color: #04ff00;">Stockfish</span> - SlowChess: Stockfish was a pawn up from the start, evals started to increase after move 20 and Stockfish placed a strong bishop on d5. SlowChess mostly waited, after opening the b file Stockfish exchanged its bishop and placed a rook on d5, then captured another pawn and created a passer. SlowChess beame desperate, it gave two more pawns to open the king side,now it faced more passers and couldn't get rid of any of them. Stockfish attacked the black king, SlowChess lost material and was mated.</p><p><a href="https://tcec-chess.com/#div=p&game=68&season=25">game 68</a>, <span style="background-color: #04ff00;">Leela</span> - RubiChess: There were only a few exchanges after the start and evals were stable. On move 29 Leela captured a pawn and evals started to increase. RubiChess opened the queen side and tried to attack but wasn't strong enough, Leela exchanged pieces and in a QRB vs QRN position captured a second pawn. After exchanging queens Leela created a passer, progress was slow but inevitable, it took Leela another 40 moves to queen a pawn and mate.</p><p><a href="https://tcec-chess.com/#div=p&game=70&season=25">game 70</a>, <span style="background-color: #04ff00;">KomodoDragon</span> - Leela: Most minor pieces were exchanged quickly and Leela castled long, KomodoDragon managed to create an advanced passer in the center. Leela was concerned with protecting its isolated pawns on the king side and only blocked the white passer. KomodoDragon's eval started to increase while Leela'a remained stable. KomodoDragon captured pawns on the king side, then gave its rook and attacked the black king. Leela's eval started to increase when it was 5 pawns down in a QN vs QRN position. Leela captured a few pawns back but lost its knight for a passer. After exchanging queens the N vs R ending 3 pawns up was a win, though it took KomodoDragon another 35 moves to complete.</p><p><a href="https://tcec-chess.com/#div=p&game=73&season=25">game 73</a>, <span style="background-color: #04ff00;">Stockfish</span> - Igel: Igel gave two pawns and opened the king side, Stockfish kept its king safe and evals started to increase. The game reached a RB vs RB position, Stockfish was a pawn up with connected passers. Stockfish pushed the passers forward and exchanged rooks, the bishops were same colored. Igel captured 3 pawns but couldn't stop a queening and mate.</p><p><a href="https://tcec-chess.com/#div=p&game=75&season=25">game 75</a>, <span style="background-color: #04ff00;">Leela</span> - SlowChess: There were no exchanges after the start, the engines formed long pawn lines across the board. SlowChess opened the h file, Leela walked its king to the queen side. Leela's eval was very high though SlowChess moved its queen and a rook forward. SlowChess gave a knight for two pawns and created connected passers on the king side, Leela exchanged pieces and gave back a bishop to capture the passers. Leela captured a pawn and created an advanced passer, SlowChess lost a bishop for th epasser and the game reached a RBN vs RN position. SlowChess lost more material and the game ended in a tablebase win. </p><p><a href="https://tcec-chess.com/#div=p&game=80&season=25">game 80</a>, <span style="background-color: #04ff00;">Stockfish</span> - Stoofvlees: Stockfish castled long and pushed pawns on the king side. Evals increased, a series of exchanges opened the king side and Stockfish gave a bishop and two pawns for a rook. Stockfish used its major pieces to attack, first it sacrificed a rook and exposed the black king, the it captured a bishop. The white queen and rook chased the black king and forced mate.</p><p><a href="https://tcec-chess.com/#div=p&game=81&season=25">game 81</a>, <span style="background-color: #04ff00;">Stoofvlees</span> - Igel: Evals were stable until move 39, Igel missed something and evals jumped. Stoofvlees opened the d file, then in a series of exchanges the engines reduced to a B vs R ending. Stoofvlees was only one pawn up but it pushed a passer to the 7th rank. It used a second passer to open the way for the white king to move forward. Stoofvless captured a pawn and created another passer, Igel lost its rook to stop it. Stoofvlees had one last pawn to win. </p><p><a href="https://tcec-chess.com/#div=p&game=82&season=25">game 82</a>, <span style="background-color: #04ff00;">Leela</span> - Stockfish: Queens were off early, evals were stable, Stockfish created a passer in teh center and the white king moved to block it. Stockfish placed a knight on c3 that interfered with the white piece movement, but was also trapped there. Leela moved its attention to the king side and evals increased. Leela managed to capture a pawn and create a passer, then it used exchanges to create two more. Stockfish couldn't stop all the passers and it lost a rook, the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=83&season=25">game 83</a>, <span style="background-color: #04ff00;">RubiChess</span> - Ethereal: Both kings remained in the center uncastled, Ethereal had difficulties to develop its king side pieces but eventually the h file opened and the engines exchanged a pair of rooks. RubiChess moved its queen forward on the king side, Ethereal was busy defending and couldn't attack the exposed white king. The engines reduced to a RB vs RB position, RubiChess captured a pawn and created a passer. Ethereal delayed but couldn't stop the passer, it lost a rook and the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=84&season=25">game 84</a>, <span style="background-color: #04ff00;">KomodoDragon</span> - SlowChess: KomodoDragon pushed a pawn to h6, it moved its king without castling. A series of exchanges opened files on the queen side and evals started to increase. The engines shuffled for a while, KomodoDragon placed its major pieces o the open files, then it gave a rook for a bishop and attacked. The game reached a RB vs RR position with the black king in the corner and a white rook on g7. The white king moved forward and the engines traded pawns, SlowChess lost a rook for a passer and the game ended in a tablebase win.</p><p><i>Standings after RR3: Stockfish +10, Leela +6, KomodoDragon +3, RubiChess -1, Ethereal -2, Stoofvlees -3, Igel -5, SlowChess -8. Stockfish lost the game in black against Leela, it continues to be perfect in white. Leela won its 3 white games, including against Stockfish, but lost in black against KomodoDragon. KomodoDragon had a good RR3 with a +2 score, compared to a -1 score in RR1.</i></p><p><a href="https://tcec-chess.com/#div=p&game=85&season=25">game 85</a>, <span style="background-color: #04ff00;">Igel</span> - SlowChess: Igel pushed pawns on the king side with evals increasing steadily. After opening the g file the white queen moved forward through the center, in a series of exchanges Igel captured a bishop and reduced to a RN vs R position. Igel had enough pawns, the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=89&season=25">game 89</a>, <span style="background-color: #04ff00;">Leela</span> - Igel: The engines castled in opposite directions and Leela pushed pawns on the king side. The engines exchanged minor pieces in the center, Leela captured a pawn and created a passer. Igel captured the passer and in a series of exchanges the game reached a QRR vs QRR position. Leela again had a passer that it slowly pushed forward. After reducing to a rook ending Leela captured a pawn and had 2 passers on the 7th rank, it forced a queening and won.</p><p><a href="https://tcec-chess.com/#div=p&game=91&season=25">game 91</a>, <span style="background-color: #04ff00;">Stockfish</span> - KomodoDragon: see featured game below</p><p><a href="https://tcec-chess.com/#div=p&game=92&season=25">game 92</a>, <span style="background-color: #04ff00;">Ethereal</span> - SlowChess: The king side was open and both engines castled long. Evals increased steadily though SlowChess moved a rook forward and captured a pawn. Queens were exchanged and Ethereal regained the pawn, then it exchanged pieces and captured two more pawns. The game reached a RB vs RB position, Ethereal slowly pushed a passer forward and SlowChess lost the bishop to stop it. The game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=95&season=25">game 95</a>, <span style="background-color: #04ff00;">KomodoDragon</span> - Stoofvlees: The engines opened the h file and exchanged a pair of rooks early. Both engines castled long and the game reached a QRB vs QRN position. KomodoDragon captured a pawn and created a passer on the king side. Stoofvlees thought it was safe for a few moves after exchanging the minor pieces, it even captured two pawns. However when it stopped to think it realized it was losing. KomodoDragon pushed the passer to the 7th rank, then pinned the black rook. Stoofvlees couldn't get out of the pin, a white pawn moved forward and captured the rook, mate followed.</p><p><a href="https://tcec-chess.com/#div=p&game=98&season=25">game 98</a>, <span style="background-color: #04ff00;">Leela</span> - KomodoDragon: KomodoDragon castled long, Leela moved a bishop forward and captured a pawn. KomodoDragon moved its major pieces to the king side but was not strong enough to attack, Leela exchanged pieces when it could and evals increased. Leela gave two pawns and opened the queen side, then traded RN for Q. In a QB vs RBN position Leela captured pawns and went two pawns up. It pushed a passer, gave its queen for a bishop and queened the passer. KomodoDragon lost material and was mated. There were two white wins in this game pair.</p><p><a href="https://tcec-chess.com/#div=p&game=99&season=25">game 99</a>, <span style="background-color: #04ff00;">Stoofvlees</span> - SlowChess: Stoofvlees castled long, SlowChess pushed pawns on the queen side and its king remained in the center. Stoofvlees tried to open the king side but SlowChess avoided exchanges until its king walked to the queen side. After opening the king side the engines traded pawns and Stoofvlees went a pawn up. The engines exchanged a pair of rooks and Stoofvlees moved a rook to the 7th rank. In a series of exchanges the engines reduced to a Q vs RN position, SlowChess lost the roo for a passer and the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=100&season=25">game 100</a>, <span style="background-color: #04ff00;">Stockfish</span> - Ethereal: The engines exchanged all knights, the queen side was open and Stockfish captured a pawn on the king side. Ethereal gave a rook for a bishop and pushed pawns in the center, after exchanging queens evals started to increase in a RRB vs RBB position. Ethereal stopped a white passer and regained the pawn, after exchanging a pair of bishops Ethereal had a passer in the center and Stockfish had two on the king side. Stockfish gave one passer but trapped the black king on the open h file. It used the threat of mate to gain material and win.</p><p><a href="https://tcec-chess.com/#div=p&game=102&season=25">game 102</a>, <span style="background-color: #04ff00;">Ethereal</span> - Stoofvlees: The engines exchanged pawns on the queen side, Ethereal's eval jumped when it gave a knight and created a passer. Stoofvlees thought it was fine for a few moves, then its eval jumped as well. Ethereal regained the piece and the game reached a RRN vs RRN position. Ethereal gave a rook for a knight and pawn, then the white king moved forward on the king side. Stoofvlees captured the passer on the queen side but could not defend the king side. After a pairof rooks was exchanged Ethereal queened a passer and mated.</p><p><a href="https://tcec-chess.com/#div=p&game=103&season=25">game 103</a>, SlowChess - <span style="background-color: #ffa400;">Leela</span>: The engines started to shuffle on move 30, with piece exchanges resetting the 50-move counter. Leela was out of time and playing on the 6 second increments, on move 152 Leela moved too late and lost on time.</p><p><a href="https://tcec-chess.com/#div=p&game=105&season=25">game 105</a>, <span style="background-color: #04ff00;">KomodoDragon</span> - Igel: Both engines did not castle their kings, there were almost no pawn exchanges after the start and both engines played behind their pawn lines. Igel placed both knights on the 4th rank and tried to hold a pawn line across the board. KomodoDragon exchanged a bishop for one of the black knights, then moved pieces to the queen side where the black king was located. The engines opened the queen side with exchanges, KomodoDragon captured two pawns and then moved it major pieces forward on the king side. The game reached a QR vs QR position with the black king on the run and a white 3 pawns up. Igel lost its queen for a rook, KomodoDragon queened a passer and mated.</p><p><a href="https://tcec-chess.com/#div=p&game=106&season=25">game 106</a>, <span style="background-color: #04ff00;">RubiChess</span> - SlowChess: Both engines castled long, evals started to increase on move 20 after SlowChess created an advanced passer in the center while RubiChess had a pawn majority on the king side. RubiChess moved a rook forward on the king side and exchanged queens, then reduced to a RBN vs RBN position. RubiChess captured the black passer and was 3 pawns up, it gained material and the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=110&season=25">game 110</a>, <span style="background-color: #04ff00;">Stockfish</span> - Leela: Evals were stable for a long time, the engines exchanged pawns and a few minor pieces. On move 32 the engines opened the queen side and evals started to increase slowly. Stockfish doubled rooks on the open c file, then created an advanced passer after an exchange. After some shuffling Stockfish gave a rook for a knight and the game reached a QRB vs QRR position. Leela couldn't get rid of the white passer, Stockfish captured two pawns and the queens were exchanged. Leela tried to delay but Stockfish was patient, eventually Leela couldn't stop the white passer, Stockfish queened and mated. There were two white wins in this game pair.</p><p><b>Featured game: Stockfish - KomodoDragon</b><br /><a href="https://tcec-chess.com/#div=p&game=91&season=25">game 91</a></p><p>Stockfish pushed pawns on the king side and castled long. it gave a pawn and opened the king side. The black king remained in the center and evals slowly increased. KomodoDragon had a rook on the open h file, Stockfish regained the pawn, then the engines exchanged a pair of rooks and queens. On move 40 Stockfish went a pawn up, its first material advantage of the game. </p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiT5XLP5yKkVgAQ7MFrKPrH1uTYmfVujAOwL--RVyystuxyM78QAyD93CiyhIJ21t6eN0ayJQb3FG9N79DF75BljFahlce7049BKULeuV0t0oQEeqPfrUjuog9NWSGNAyYLWQVNfBroSqhsoLsflmvHeDyqRQEJP_kBs1d-ds0e5RY2aRox8ENYPOErp2w/s1161/pic1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="693" data-original-width="1161" height="382" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiT5XLP5yKkVgAQ7MFrKPrH1uTYmfVujAOwL--RVyystuxyM78QAyD93CiyhIJ21t6eN0ayJQb3FG9N79DF75BljFahlce7049BKULeuV0t0oQEeqPfrUjuog9NWSGNAyYLWQVNfBroSqhsoLsflmvHeDyqRQEJP_kBs1d-ds0e5RY2aRox8ENYPOErp2w/w640-h382/pic1.jpg" width="640" /></a></div><br /><div class="separator" style="clear: both; text-align: left;">Stockfish had one passer, still on its initial square. Progress was slow in a difficult middlegame, the black bishop pair was strong in an open board. KomodoDragon wanted to separate the white pawns on the queen side, on move 54 it gave a rook for a knight and captured the b pawn. In a RBN vs BBN position KomodoDragon blocked the white passer and Stockfish captured a pawn. </div><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg00AiXVB8rR_srJ8keYupjS0SSH64C8ugAlZAJppzAmwCQ0sMvkKWw94yfQk5t5D8CMEHRnF1GCzQmYAVeS_Zj7c1mhGiLulSBc13WqYLeamaBrH4Wtoj63SK3KQ5qltib1nvRjIJsDRp9ZJ0uuXGNlSaH1wTXWJWIuhRLwuawar3HFRjLaRR1d83GP4U/s1168/pic2.jpg" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="697" data-original-width="1168" height="382" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg00AiXVB8rR_srJ8keYupjS0SSH64C8ugAlZAJppzAmwCQ0sMvkKWw94yfQk5t5D8CMEHRnF1GCzQmYAVeS_Zj7c1mhGiLulSBc13WqYLeamaBrH4Wtoj63SK3KQ5qltib1nvRjIJsDRp9ZJ0uuXGNlSaH1wTXWJWIuhRLwuawar3HFRjLaRR1d83GP4U/w640-h382/pic2.jpg" width="640" /></a></p><p>Progress was again slow, pushing the passer required a lot of preparation. On move 72 Stockfish pushed the passer the the 5th rank, on move 78 Stockfish gave back the rook for a bishop but then its passer was unstoppable. Stockfish queened the passer and mated.</p><p><br /></p>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com0tag:blogger.com,1999:blog-4430065842059358622.post-14331880309937897672023-09-11T01:30:00.006+03:002023-09-12T00:22:19.039+03:00Season 25 premier division, after RR2<p><b>Standings after RR2</b></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgxHNrifszyU6vPlqEmZnJ0-Xaagmd-PZfw0Iv1mh079n8mXjNdlhoNS2hC1RPOmUWgZ9u7lzO_onZY-jkOEkUi02FY40C1qI2robOBE4-DDgY6jmvJwDNstJBDUsr6nIb374zTpjmt0p20WhDLwqn9I9WmUZ0QHisVi0nIo3K0dWFlXvUx1b8yNfw9iFk/s870/Screenshot_20230910-121258_Chrome.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="766" data-original-width="870" height="353" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgxHNrifszyU6vPlqEmZnJ0-Xaagmd-PZfw0Iv1mh079n8mXjNdlhoNS2hC1RPOmUWgZ9u7lzO_onZY-jkOEkUi02FY40C1qI2robOBE4-DDgY6jmvJwDNstJBDUsr6nIb374zTpjmt0p20WhDLwqn9I9WmUZ0QHisVi0nIo3K0dWFlXvUx1b8yNfw9iFk/w400-h353/Screenshot_20230910-121258_Chrome.jpg" width="400" /></a></div><br /><p>Stockfish had a perfect DRR with 7/7 game pair wins, Leela was perfect against the bottom5 engines but lost to Stockfish and drew against KomodoDragon. So far it is not clear whether to include KomodoDragon in the leader group, it only had 2/5 game pair wins against the bottom5 engines. At the bottom SlowChess is the only engine without a game pair win so far. RubiChess advanced from league 1 and it may be strong enough to stay in the premier division this season.</p><p><b>Interesting games</b></p><p><a href="https://tcec-chess.com/#div=p&game=3&season=25">game 3</a>, <span style="background-color: #04ff00;">Stockfish</span> - RubiChess: The engines castled in opposite directions, RubiChess gave a pawn and tried to attack the queen side. Stockfish moved pieces to protect its king, RubiChess decided to give a bishop for pawns and expose the white king. It then gave a rook for a bishop to clear the last white pawn on the queen side. Stockfish found safety for its king with a pair of knights blocking files. After exchaging queens the attack was over and Stockfish was a rook up, RubiChess lost more material and was mated.</p><p><a href="https://tcec-chess.com/#div=p&game=6&season=25">game 6</a>, <span style="background-color: #04ff00;">RubiChess</span> - Stoofvlees: RubiChess captured a pawn on the queen side, Stoofvlees tried to attack on the king side. RubiChess was strong enough to keep its king safe but Stoofvlees did not change its plan. RubiChess captured 3 more black pawns and gave a rook for a bishop. Stoofvlees gave pieces to expose the white king, RubiChess avoided perpetual check and forced mate on the other side of the board.</p><p><a href="https://tcec-chess.com/#div=p&game=9&season=25">game 9</a>, <span style="background-color: #04ff00;">Ethereal</span> - Igel: Ethereal gave a pawn and that was the only capture after the start. The engines shuffled with stable evals until move 51, Igel gave the pawn back and the first pieces were exchanged on move 58. Evals started to increase a few moves later, after some more exchanges Ethereal was a pawn up with a passer on the queen side. Twice Ethereal left a piece hanging and Igel refused to take, probably related to king safety. Evals continued to increase, Ethereal opened the king side and captured two pawns. Igel couldn't protect its king and block passers without losing material, Ethereal queened and mated.</p><p><a href="https://tcec-chess.com/#div=p&game=10&season=25">game 10</a>, <span style="background-color: #04ff00;">Stockfish</span> - SlowChess: There was one pawn exchange after the start and the engines played mostly behind their pawn lines. Evals slowly increased, then jumped when Stockfish gave a bishop for pawns and exposed the black king. SlowChess exchanged pieces and stopped the attack, the result was a BN vs pawns position. Stockfish captured the black passers and the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=12&season=25">game 12</a>, <span style="background-color: #04ff00;">Leela</span> - RubiChess: Leela gradually increased the pressure on the king side while evals increased, eventually the black king was left without pawn support. The game reached a QRB vs QRB position, Leela went a pawn up and exchanged queens. RubiChess couldn't stop the connected white passers advancing, Leela queened and mated.</p><p><a href="https://tcec-chess.com/#div=p&game=15&season=25">game 15</a>, <span style="background-color: #04ff00;">SlowChess</span> - Stoofvlees: SlowChess castled long, Stoofvlees pushed pawns on the queen side and tried to attack. It gave a knight for pawns and opened the center files but SlowChess kept its king safe. SlowChess moved its rooks forward and countered with an attack on the black king. Stoofvlees lost material and the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=17&season=25">game 17</a>, <span style="background-color: #04ff00;">Stockfish</span> - Igel: The center was blocked and both engines castled long. Igel struggled to develop its king side pieces, it gave a knight for a pawn to open the queen side. Stockfish gave a rook to get rid of a strong knight, Igel's DS bishop finally moved and was exchanged. Stockfish captured a pawn, then used a pawn majority on the king side to create an advanced passer. After exchaging queens Igel was forced to lose material for the passer, the game reached a winning RB vs R ending.</p><p><a href="https://tcec-chess.com/#div=p&game=18&season=25">game 18</a>, <span style="background-color: #04ff00;">Stoofvlees</span> - Ethereal: There were many early exchanges and the game reached a RRB vs RRB position. Evals started to increase though material was equal, all rooks were exchanged and Stoofvlees captured a pawn. Ethereal tried to cover threats on both sides of the board and Stoofvlees captured the pawns in the center, the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=19&season=25">game 19</a>, <span style="background-color: #04ff00;">Leela</span> - SlowChess: The engines opened the center, Leela gave a pawn but its bishops had a clear view of the king side corner. SlowChess tried to protect its king, Leela gave another pawn and then regained it and created an advanced passer in the center. SlowChess tried to counter with its passers, but it had to defend against a pawn on the 7th rank and its king was under threat. SlowChess lost material and the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=20&season=25">game 20</a>, <span style="background-color: #04ff00;">RubiChess</span> - KomodoDragon: KomodoDragon castled long, RubiChess opened the a file and doubled its rooks there. For a long while the engines shuffled with stable evals, after move 75 the engines started to exchange pieces and pawns. KomodoDragon gave a rook for a knight and evals started to increase. The game reached a RB vs BN position, after trading most pawns RubiChess had two doubled pawns and KomodoDragon had one. KomodoDragon defende its last pawn and avoided a 7-man tablebase loss. RubiChess pushed the black king to the back rank, moved its king forward and mated.</p><p><a href="https://tcec-chess.com/#div=p&game=24&season=25">game 24</a>, <span style="background-color: #04ff00;">Stockfish</span> - Stoofvlees: Evals slowly increased and Stockfish went a pawn up. Stoofvlees gave a knight and tried to attack through the center. Stockfish gave the pieces back but it was two pawns up. The white king was exposed in the center but Stoofvlees' attack was not strong enough, the game reached a RRB vs RRB position with white 3 pawns up and ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=25&season=25">game 25</a>, <span style="background-color: #04ff00;">Stoofvlees</span> - Igel: The engines castled in opposite directions, Stoofvlees opened the king side and the game reached a QRR vs QRR position. Stoofvlees captured a pawn, Igel thought it was quite safe until queens were exchanged. Stoofvlees managed to capture another pawn and get its king forward. It pushed a passer to the 7th rank and Igel lost a rook for it. The game ended in a tablebase win.</p><p><i>Standings after RR1: Stockfish +4, Leela +2, Ethereal RubiChess 0, KomodoDragon SlowChess Stoofvlees -1, Igel, -3. Stockfish and Leela have an early lead, the only engines with a positive score and no loss so far. Stockfish won all its game in white in the RR, Leela had one less game in white and one of those was a draw against Stockfish. KomodoDragon lost a game against RubiChess and has no wins, but 2/3 of its games in white were against the leaders. It may still move up in the table, though it's too early to tell. We may not have a top3 this season but a top2. </i></p><p><a href="https://tcec-chess.com/#div=p&game=29&season=25">game 29</a>, <span style="background-color: #04ff00;">Igel</span> - SlowChess: Evals increased after move 20, the game reached a RRN vs RRB position. Igel captured a pawn and also pinned the black bishop. SlowChess couldn't get out of the pin, eventually Igel captured the bishop. Igel captured the remaining black pawns for the knight, the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=30&season=25">game 30</a>, <span style="background-color: #04ff00;">KomodoDragon</span> - Ethereal: KomodoDragon captured a pawn and created a pawn majority on the queen side. The white king was castled long, Ethereal moved major pieces to threaten an attack, after a pawn exchange KoodoDragon had connected passers. Evals gradually increased as KomodoDragon exchanged pieces, the game reached a RBN vs RBB position. KomodoDrago reduced to a same colored bishop ending, Ethereal lost the bishop for a passer and the game ended in a tablebase win. </p><p><a href="https://tcec-chess.com/#div=p&game=32&season=25">game 32</a>, <span style="background-color: #04ff00;">Leela</span> - Stoofvlees: Leela captured a pawn and the game reached a RBN vs RBN position. Stoofvlees regained the pawn but its knight was far on the king side almost trapped. By the time Stoofvlees moved the knight back Leela cleared the black pawns on the queen side. Both engines had passers, after reducing to a knight ending there was a promotion race. Stoofvlees was a pawn up but Leela queened first followed by mate.</p><p><a href="https://tcec-chess.com/#div=p&game=33&season=25">game 33</a>, <span style="background-color: #04ff00;">Leela</span> - Igel: The engines opened the queen side and evals started to increase. After the g file opened Leela had time to move its king away from the king side while Igel dealt with potential threats on its back rank. After exchanging queens Leela captured a pawn and created a passer in a RBN vs RBN position. Igel lost material and the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=35&season=25">game 35</a>, <span style="background-color: #04ff00;">Stockfish</span> - KomodoDragon: There were only a few exchanges after the start, Stockfish captured a pawn on the queen side and KomodoDragon tried to attack on the king side. KomodoDragon opened the g file and doubled its rooks there, Stockfish exchanged a pair of rooks and kept its king safe. After more piece exchanges the game reached a RNN vs RBN position, Stockfish created a passer and KomodoDragon gave a knight to stop it. Stockfish captured more pawns, queened a passer and mated.</p><p><a href="https://tcec-chess.com/#div=p&game=36&season=25">game 36</a>, <span style="background-color: #04ff00;">Ethereal</span> - SlowChess: Ethereal created a passer on the queen side and SlowChess created a passer in the center. After exchanging queens SlowChess gave its bishop to capture the white passer, Ethereal captured the black passer and reduced to a RBN vs RN position. Ethereal captured pawns, SlowChess lost its rook for a passer and the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=37&season=25">game 37</a>, <span style="background-color: #04ff00;">Igel</span> - Ethereal: Igel trapped a black knight on the king side, then captured a pawn on the queen side and created a passer. Evals increased though there were no exchanges, the first pieces were exchanged on move 40. Igel moved a rook forward and pushed the passer, Ethereal freed its knight and it crossed the board. The game reached a BN vs BN position, Ethereal lost the knight for the passer. Ethereal avoided a 7-man position, Igel queened a passer and mated. There were two white wins in the game pair.</p><p><a href="https://tcec-chess.com/#div=p&game=43&season=25">game 43</a>, <span style="background-color: #04ff00;">Stoofvlees</span> - SlowChess: Stoofvlees castled long, SlowChess pushed pawns on the queen side but slowly and without pieces to back them. One pawn reached a3 and the rest were blocked. Evals started to increase, SlowChess captured a pawn and then Stoofvlees captured two. The b file opened but Stoofvlees walked its king to the king side for safety. SlowChess gave a rook for a bishop and the a pawn became an advanced passer, the game reached a RRB vs RNN position. While SlowChess protected its king and passer Stoofvlees pushed connected passers forward. Stoofvlees captured the black a pawn and pushed a 3rd passer, SlowChess lost material and the game ended in a tablebase win. There were two white wins in this game pair.</p><p><a href="https://tcec-chess.com/#div=p&game=44&season=25">game 44</a>, <span style="background-color: #04ff00;">Stockfish</span> - Ethereal: There was a lot of shuffling after the start, the first piece exchange was on move 35. Stockfish had a bishop pair advantage, evals started to increase after move 48. Ethereal captured a pawn and opened the center, the game reached a QRB vs QRN position, Stockfish regained the pawn and created a passer. The engines reduced to a queen ending, Stockfish kept its king safe and pushed a passer forward, the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=p&game=46&season=25">game 46</a>, <span style="background-color: #04ff00;">Ethereal</span> - Stoofvlees: There were many early exchanges and the game reached a QRN vs QRN position. Ethereal's evals started to increase, Stoofvlees saw the problem a few moves later. Ethereal moved its pieces forward to attack the black king, in a series of exchanges the engines reduced to a king and pawns ending. Each engines had 3 pawns, Ethereal's two connected pawns on the king side forced the black king to move there, leaving the black pawns on the queen side unprotected, game over. There were two white wins in this game pair. </p><p><a href="https://tcec-chess.com/#div=p&game=48&season=25">game 48</a>, <span style="background-color: #04ff00;">KomodoDragon</span> - RubiChess: Both engines castled long, evals slowly increased though RubiChess captured a pawn. KomodoDragon increased the pressure on the queen side and then gave a rook for a bishop and pawn to open the b file. The black king ran to the king side, after a series of exchanges RubiChess gave back the material and the game reached a RBN vs RNN position. KomodoDragon pinned a knight on the back rank and then it captured the knight. The game reached a tablebase win 20 moves later. There were two white wins in this game pair. </p><p><a href="https://tcec-chess.com/#div=p&game=49&season=25">game 49</a>, <span style="background-color: #04ff00;">KomodoDragon</span> - Igel: There were no exchanges until the engines opened the king side on move 25, KomodoDragon went up a pawn and evals started to increase. Igel had strong pawns in the center but its king was exposed. KomodoDragon had passers on the queen side, in a series of exchanges Igel lost a bishop and all the queen side pawns were cleared. KomodoDragon attacked the black king, Igel had a passer on the 7th rank but was not on time to stop being mated.</p><p><a href="https://tcec-chess.com/#div=p&game=50&season=25">game 50</a>, <span style="background-color: #04ff00;">RubiChess</span> - SlowChess: SlowChess pushed pawns on the queen side, after exchanging queens SlowChess created a passer there while RubiChess created a passer in the center. RubiChess blocked the black passer and moved its rooks forward, then captured a pawn and pushed the passer to the 7th rank. SlowChess lost its passer and another pawn, then lost a piece for the white passer and the game ended in a tablebase win. </p><p><a href="https://tcec-chess.com/#div=p&game=51&season=25">game 51</a>, <span style="background-color: #04ff00;">Leela</span> - Ethereal: The white king was unable to castle, yet after Ethereal opened the d file evals slowly increased. The black queen moved forward on the king side but Leela kept its king safe. There was some action on the queen side, the b file opened and Ethereal created a passer. Then on the king side the h file was half opened, the black queen had to stay there to stop potential attacks. Leela had an advantage on the queen side, it captured a pawn and created a passer. Leela gave a rook for a bishop and captured the remaining black pawns on the queen side, then pushed its passer to the 7th rank. Ethereal lost material and the game ended just before mate.</p><p><a href="https://tcec-chess.com/#div=p&game=54&season=25">game 54</a>, <span style="background-color: #04ff00;">Stockfish</span> - Leela: see featured game below.</p><p><a href="https://tcec-chess.com/#div=p&game=55&season=25">game 55</a>, <span style="background-color: #04ff00;">Ethereal</span> - RubiChess: The engines castled in opposite directions, evals increased from the start as Ethereal prepared an attack on the king side. RubiChess captured 3 pawns and gave a knight, the black king was safe but Ethereal reduced to a RBN vs RB position. Ethereal captured pawns and exchanged bishops, RubiChess had a passer on the 2nd rank but couldn't hold on to it. The game ended in a tablebase win.</p><p><b>Featured game: Stockfish - Leela</b><br /><a href="https://tcec-chess.com/#div=p&game=54&season=25">game 54</a></p><p>Evals were stable for a long time after the start. Stockfish castled long and pushed pawns on the king side, one pawn reached h6. Leela pushed pawns on the queen side but eventually castled long as well. Leela captured a pawn, its king side rook couldn't develop for a while. After a pawn trade the white h pawn became as advanced passer. Leela freed its rook and Stockfish exchanged queens.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEggway3CvPj_wNBEK43rpeDpk9bsH1upNuedMUUJLXM556HGD9ZdQPEqLTmgo3-n3jPSvsXTvU0QtNLPSsP_91yeQx0mGsUPOIoN74GBte190f6EPEeOm6QasSTLm-KLrntz4xmlxB8fH1uoqh2gxv3H9jcxS48K-ULYO4Da4IOm5HCrbFrhSm-0Gzv8lw/s1192/pic1.png" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="697" data-original-width="1192" height="374" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEggway3CvPj_wNBEK43rpeDpk9bsH1upNuedMUUJLXM556HGD9ZdQPEqLTmgo3-n3jPSvsXTvU0QtNLPSsP_91yeQx0mGsUPOIoN74GBte190f6EPEeOm6QasSTLm-KLrntz4xmlxB8fH1uoqh2gxv3H9jcxS48K-ULYO4Da4IOm5HCrbFrhSm-0Gzv8lw/w640-h374/pic1.png" width="640" /></a></div><p>Stockfish's eval slowly increased while Leela's eval remained stable. Leela kept its rooks on the back rank to prevent a queening, Stockfish captured a pawn and exchanged a pair of rooks. In a RN vs RB position Stockfish traded pawns on the queen side. Material was equal and Leela was still not convinced.</p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjjklv_nKLnsBcTWxzWXKjyyJvg5f3sMrQNf0TBys5YGL1YOnMiQt0LKcx1tmtrnR1MoHlNbOGc0-mZUvYzfwmq-auTaNeaca7OvKmDlqCavLhsNl3T7VfEMbYyuzJ-8rR2n920ZIoOxkxolyRwfSxJ1J5-TDmO0mUqb4zkA5w7QEt926Eq0JLjYcsyhr4/s1186/pic2.png" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" data-original-height="699" data-original-width="1186" height="378" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjjklv_nKLnsBcTWxzWXKjyyJvg5f3sMrQNf0TBys5YGL1YOnMiQt0LKcx1tmtrnR1MoHlNbOGc0-mZUvYzfwmq-auTaNeaca7OvKmDlqCavLhsNl3T7VfEMbYyuzJ-8rR2n920ZIoOxkxolyRwfSxJ1J5-TDmO0mUqb4zkA5w7QEt926Eq0JLjYcsyhr4/w640-h378/pic2.png" width="640" /></a></p><p>Stockfish captured the black c pawn and pushed its passer to the 7th rank. Leela blocked with its rook and its eval started to increase. The white king and c pawn moved forward, when it was ready Stockfish abandoned its h pawn and captured the black a pawn. Leela couldn't stop the c pawn advancing, it lost material and the game ended in a tablebase win.</p><p><br /></p>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com0tag:blogger.com,1999:blog-4430065842059358622.post-28157872180167906172023-09-07T01:18:00.001+03:002023-10-10T13:24:54.852+03:00Season 25 league 1 statistics<p>A summary <a href="https://drive.google.com/open?id=1dpikbAHWxz1wLcsOzG0kxKCk0Hn67IYJPL8B1wzj_rk" target="_blank">statistics table</a> of previous stages and seasons. </p><p><b>Draw rate, wins</b></p><p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhQFi0ECOkLRPe1vTUSw5PKDLCtXsKejG3LkRBYnTPwIS1wbcKCiQohsf6e36pCqoOWbycVcPKY4GIlcg-bmvw1pDzTceojnmVW4IivPhF1SITDXqZcmQybK6R7iPEZxrTw05w94Z7WjM1DYXUizyyXPYilEXAtEfQNy_ZHNHeV6ZumhA1GXpePkOwg4KM/s480/S25.l1.g1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhQFi0ECOkLRPe1vTUSw5PKDLCtXsKejG3LkRBYnTPwIS1wbcKCiQohsf6e36pCqoOWbycVcPKY4GIlcg-bmvw1pDzTceojnmVW4IivPhF1SITDXqZcmQybK6R7iPEZxrTw05w94Z7WjM1DYXUizyyXPYilEXAtEfQNy_ZHNHeV6ZumhA1GXpePkOwg4KM/s320/S25.l1.g1.jpg" width="320" /></a></div>Final draw rate was 47.7%. <p></p><p><b>Game termination</b><br /><br />The three most common game termination causes were:<br />39.0% - TCEC draw rule<br />39.0% - SyzygyTB<br />15.2% - Mate<br /><br />There were 3 crashes in the stage, Seer crashed on time 3 times.<br /></p><p><b>Moves per game</b></p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEibi-L4iZymbFzn-zWOmhxYNpZzAGP45sRLXIVUv5QpRZzki7J0TjDT_GPHOJnOspdRQbFKRGRGlGiLk4lDVBViuqgcprwkfgam5YCJn29mKlATXoRikA4w45yuX3DTO0sp3pkPeuAPnUu7-f6WZG_P2VAougfzOSxOkbGkBQbtu4hHVNz1TRHyT4ABZ3w/s480/S25.l1.g2.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEibi-L4iZymbFzn-zWOmhxYNpZzAGP45sRLXIVUv5QpRZzki7J0TjDT_GPHOJnOspdRQbFKRGRGlGiLk4lDVBViuqgcprwkfgam5YCJn29mKlATXoRikA4w45yuX3DTO0sp3pkPeuAPnUu7-f6WZG_P2VAougfzOSxOkbGkBQbtu4hHVNz1TRHyT4ABZ3w/s320/S25.l1.g2.jpg" width="320" /></a></p><p>Median= 70.5<br />Average= 72.7<br /><br />There were 31 games longer than 100 moves, the longest was 180 moves (DeepSjeng - Seer, game 21, draw). <br /><br /><b>Time per game (hours)</b></p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg5d4UXDhdKWZno8BDQjHWFQYKty4bUVBFBglolrNy3RDogXJLd1_9PKahGGTHt-EbzyLUyaCF-6i4wLoWf4Vxh3HaXfQZzV6uOMpYQQm3IdDzKNjJ6ewPBsia_cTSZ6kDnQ7gDWRkQeICh0pWqSH12FfD_RWrdux1QRu0Y5jcROKBJmhzEm0w-dJji15Q/s480/S25.l1.g3.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg5d4UXDhdKWZno8BDQjHWFQYKty4bUVBFBglolrNy3RDogXJLd1_9PKahGGTHt-EbzyLUyaCF-6i4wLoWf4Vxh3HaXfQZzV6uOMpYQQm3IdDzKNjJ6ewPBsia_cTSZ6kDnQ7gDWRkQeICh0pWqSH12FfD_RWrdux1QRu0Y5jcROKBJmhzEm0w-dJji15Q/s320/S25.l1.g3.jpg" width="320" /></a></p><p>Median= 1:04<br />Average= 1:03<br /><br /><b>Openings</b><br /><br />There were variable length book openings in this stage. The first letter of the ECO codes was distributed as follows: </p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEihVxb9BDfzzJKT3EZ5UGClTYaYKFnRPpA-SYiTFG1w4_o3zbtGuj1U2faErxTaSTpi5OELVIciruLHzEV7VnKwYSn7WUT6AaKmx1xx4hWLHF82C1eM6spaXB7m7EPxWBhK-qYcZHa5e050wNCaF6KnjPaohmvdbliofgNM4Ohp-5SbOyVc7WUrIT7-tHA/s480/S25.l1.g4.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEihVxb9BDfzzJKT3EZ5UGClTYaYKFnRPpA-SYiTFG1w4_o3zbtGuj1U2faErxTaSTpi5OELVIciruLHzEV7VnKwYSn7WUT6AaKmx1xx4hWLHF82C1eM6spaXB7m7EPxWBhK-qYcZHa5e050wNCaF6KnjPaohmvdbliofgNM4Ohp-5SbOyVc7WUrIT7-tHA/s320/S25.l1.g4.jpg" width="320" /></a></p><p>The engines had almost no freedom to choose the opening variant, all of the game pairs repeated the same ECO code and the opening variant twice. <br /></p><p><b>Reverse pairs, wins</b></p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgSmh6UFFV2WbFJ0iXXQjV47v3eu0EbzSQaztxnDoyWmxgw_4hPEjMua8bveNP1JZtWSKNERUjBKJjUc9dBQqREPLcjM0wUGIB-hoSOLgE3eIDTxykjpSE3zhGafHpjNhCaBL8p-FxeCz1Uc12GwKfFmZGXorvlLny4o-WddYx7S05Kro23fhJpJbV5_c0/s480/S25.l1.g5.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgSmh6UFFV2WbFJ0iXXQjV47v3eu0EbzSQaztxnDoyWmxgw_4hPEjMua8bveNP1JZtWSKNERUjBKJjUc9dBQqREPLcjM0wUGIB-hoSOLgE3eIDTxykjpSE3zhGafHpjNhCaBL8p-FxeCz1Uc12GwKfFmZGXorvlLny4o-WddYx7S05Kro23fhJpJbV5_c0/s320/S25.l1.g5.jpg" width="320" /></a></p><p></p><div style="-webkit-text-stroke-width: 0px; color: black; font-family: "Times New Roman"; font-size: medium; font-style: normal; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: left; text-decoration-color: initial; text-decoration-style: initial; text-decoration-thickness: initial; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px;"></div><p></p><p style="-webkit-text-stroke-width: 0px; color: black; font-style: normal; font-variant-caps: normal; font-variant-ligatures: normal; letter-spacing: normal; orphans: 2; text-align: left; text-decoration-color: initial; text-decoration-style: initial; text-decoration-thickness: initial; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px;"><span style="font-family: times; font-size: small;"><b>Reverse pairs, same moves</b></span></p><p style="-webkit-text-stroke-width: 0px; color: black; font-family: "Times New Roman"; font-size: medium; font-style: normal; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: left; text-decoration-color: initial; text-decoration-style: initial; text-decoration-thickness: initial; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh6DXjQMuBhVLd06lZI4ic7VhgYxGtmlgiieamoZUKl6JitgCWFlteVM5EH0F5NgFNEZEJy3Zn_jjH2g7nMHhGxdsiFFr1ldjqdokTfEYI8PEqqYsP9ry5aUCyhTJBDApmYzt85WTBaCPbj1Bt5l5gdWWbZEeNDfj_wjxjp-U7W2CykR-sWgiIUjdugEIg/s480/S25.l1.g6.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh6DXjQMuBhVLd06lZI4ic7VhgYxGtmlgiieamoZUKl6JitgCWFlteVM5EH0F5NgFNEZEJy3Zn_jjH2g7nMHhGxdsiFFr1ldjqdokTfEYI8PEqqYsP9ry5aUCyhTJBDApmYzt85WTBaCPbj1Bt5l5gdWWbZEeNDfj_wjxjp-U7W2CykR-sWgiIUjdugEIg/s320/S25.l1.g6.jpg" width="320" /></a></p><p>Pairs of reverse games diverged less quickly than usual, 13.6% diverged immediately out of book, 53.0% of the pairs diverged at most after 1 move. The longest repeated sequence of moves was 20 plys (Seer - Viridithas, games 6 and 72, QGD Marshall defence, Seer won as white) </p><p><br /></p>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com0tag:blogger.com,1999:blog-4430065842059358622.post-16105447137563417282023-08-29T00:55:00.030+03:002023-09-07T00:41:20.321+03:00Season 25 league 1<p><b>Final Standings</b></p><p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjn2VUQHjDFfaGv83ffhcICixSkxz6BGsmyFSp9s0EdFvRtPGIpCmzAEqmWDF8wLbgI1wzURht6MXX4Fz8poklLRzSRXXaEsBVxcdPhFwszHzyD-BSCpa-qL23X_qhrrOQPq46GyV1dOMr7E2o1pAUiZ7j5jP7eZ3ubwzB-EaddcGCjfsUuFEy1De2vto8/s963/tab.png" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="963" data-original-width="610" height="640" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjn2VUQHjDFfaGv83ffhcICixSkxz6BGsmyFSp9s0EdFvRtPGIpCmzAEqmWDF8wLbgI1wzURht6MXX4Fz8poklLRzSRXXaEsBVxcdPhFwszHzyD-BSCpa-qL23X_qhrrOQPq46GyV1dOMr7E2o1pAUiZ7j5jP7eZ3ubwzB-EaddcGCjfsUuFEy1De2vto8/w406-h640/tab.png" width="406" /></a></div><br /><p style="text-align: left;">RubiChess and Igel advance to the premier division. RubiChess led from the start, it had two RRs with a perfect performance where it won all 6 games as white (with opening bias) and drew all 5 games in black (against opening bias). RubiChess beat all other engines at least once in a game pair, it had only two losses and won both reverse games. Several engines were in the race for 2nd place, though at the halfway point rofChade and Igel opened a gap to the rest of the field. rofChade was 2nd with a small margin, it also beat Igel in their first direct game pair. In the last RR rofChade lost a few games against lower ranked engines while Igel had its best RR with 6 wins including one against RubiChess. Igel's only loss was again to rofChade, but this time Igel managed to stay in the lead and hold on to 2nd place. </p><p style="text-align: left;">The 4 engines that started in the entrance league did not advance further in season 25. DeepSjeng and Viridithas struggled in league 1 and both finished in the 4 bottom places destined for relegation - if there are no surprises in the next season. Caissa and Clover had better results but they couldn't keep up with the three leaders. They should start next season in league 1.</p><p style="text-align: left;">Seer crashed three times in the league, losing games on time. In one game it was losing anyway, but in two games against rofChade and Clover the position was drawn and Seer gifted wins by crashing. In the end this half point to rofChade did not change the race for 2nd place.</p><div><p></p><p>The two qualifiers will play in the premier division together with Stockfish, Leela, KomodoDragon, Ethereal, Stoofvlees and SlowChess, all played in the premier division of season 24. This season the premier division will be a 6DRR event, followed by a 4DRR playoff of the top 4 engines.</p><p><b>Interesting games</b></p><p><a href="https://tcec-chess.com/#div=l1&game=3&season=25">game 3</a>, <span style="background-color: #04ff00;">Revenge</span> - DeepSjeng: The game reached a QRR vs QRR position, evals were mostly stable. All pieces were concentrated on the king side, DeepSjeng played inaccurately and Revenge exchanged all pieces. DeepSjeng realized it was losing the king and pawns (equal material) ending too late.</p><p><a href="https://tcec-chess.com/#div=l1&game=5&season=25">game 5</a>, <span style="background-color: #04ff00;">RubiChess</span> - Clover: The center was blocked, RubiChess opened a file on the queen side and moved a rook to the 7th rank. The engines reduced to a RB vs RB position, RubiChess pinned the black bishop on the back rank and captured a pawn. Clover couldn't avoid losing more pawns and then its pieces, and finally mate.</p><p><a href="https://tcec-chess.com/#div=l1&game=6&season=25">game 6</a>, <span style="background-color: #04ff00;">Seer</span> - Viridithas: By move 35 only one pair of pawns and a few minor pieces were exchanged. Seer attacked from the queen side and created connected passers in the center. Viridithas lost a bishop to stop the passers and the game reached a RB vs R position. Viridithas was 3 pawns up, Seer was careful to keep one last pawn. The game ended in a tablebase win 45 moves later.</p><p><a href="https://tcec-chess.com/#div=l1&game=11&season=25">game 11</a>, <span style="background-color: #04ff00;">rofChade</span> - Revenge: The engines opened the center and exchanged pieces, the game reached a RB vs RB position with white a pawn up. Revenge thought it was quite safe until rofChade exchanged rooks. Revenge regained the pawn but its king was too far to help block a passer. rofChade won the black bishop for the passer and still had one pawn to win the game.</p><p><a href="https://tcec-chess.com/#div=l1&game=16&season=25">game 16</a>, <span style="background-color: #04ff00;">RubiChess</span> - DeepSjeng: RubiChess was a pawn up, evals increased after move 30, then came back down after the game reached a QB vs QN position. DeepSjeng seemed to equalize and the engines shuffled for a while, but RubiChess' eval increased again. I'm not sure if DeepSjeng blundered or RubiChess found the right moves, RubiChess created a passer and exchanged queens. DeepSjeng lost the knight for the passer and the game ended in a tablebase win. </p><p><a href="https://tcec-chess.com/#div=l1&game=17&season=25">game 17</a>, <span style="background-color: #04ff00;">Seer</span> - Caissa: The center was blocked and there were only a few exchanges after the start. On move 49 Seer opened the h file, the black king ran to the queen side and Seer managed to capture a pawn and create an advanced passer. In a QRB vs QRN position Caissa lost its rook for the passer, the game ended in a tablebase win. </p><p><a href="https://tcec-chess.com/#div=l1&game=18&season=25">game 18</a>, <span style="background-color: #04ff00;">Viridithas</span> - Clover: The engines castled in opposite directions, Viridithas pushed pawns on the king side and created a passer in the center. The engines exchanged pieces and reduced to a RB vs RB position, Clover lost the bishop for the passer and the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=l1&game=19&season=25">game 19</a>, <span style="background-color: #04ff00;">Igel</span> - Clover: Most pieces stayed on the board, Clover moved its king without castling and the king side rook couldn't develop. After mover 45 the engines opened the board and exchanged pieces until only RB vs RB were left, Igel was a pawn up with an advanced passer. Clover exchanged rooks but Igel captured two more pawns, enough to win the opposite color bishops ending.</p><p><a href="https://tcec-chess.com/#div=l1&game=20&season=25">game 20</a>, <span style="background-color: #04ff00;">Caissa</span> - Viridithas: The engines exchanged a few minor pieces and Caissa went a pawn up. The engines mostly shuffled for a while in a RBN vs RBN position, then the white king moved forward and Caissa created a passer. Caissa captured a second pawn and reduced to a winning N vs B ending.</p><p><a href="https://tcec-chess.com/#div=l1&game=27&season=25">game 27</a>, <span style="background-color: #04ff00;">RubiChess</span> - ScorpioNN: After a series of exchanges in the center RubiChess was up a pawn with connected passers. ScorpioNN also had a passer but the white passers were stronger. RubiChess gave two minors to queen a passer, ScorpioNN gave material back to avoid mate and the end result was QR vs QB position. ScorpioNN had a passer on the 2nd rank but its king was exposed and it was busy defending. RubiChess exchanged queens and captured the passer, then reduced to a winning king and pawns ending.</p><p><a href="https://tcec-chess.com/#div=l1&game=30&season=25">game 30</a>, <span style="background-color: #04ff00;">Clover</span> - Caissa: The engines exchanged pieces until reaching a rook ending. Clover was a pawn up, it captured a second pawn to win.</p><p><a href="https://tcec-chess.com/#div=l1&game=31&season=25">game 31</a>, <span style="background-color: #04ff00;">Igel</span> - Caissa: The black king remained in the center, Caissa developed its king side rook through the h file. Caissa gave the rook for a knight and attacked the white king, the engines reduced to a QB vs Q position with black 3 pawns up. Igel played patiently, it kept one pawn and forced a queen exchange. The game ended in a tablebase win after 25 moves.\</p><p><a href="https://tcec-chess.com/#div=l1&game=33&season=25">game 33</a>, <span style="background-color: #04ff00;">rofChade</span> - Viridithas: Viridithas grabbed a pawn early but rofChade had a space advantage and evals increased gradually. rofChade pinned a bishop on the back rank, Viridithas gave a rook for a bishop to avoid losing a piece. The game reached a RN vs BB position, rofChade had an advanced passer and Viridithas lost a bishop to stop it. The game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=l1&game=34&season=25">game 34</a>, <span style="background-color: #04ff00;">ScorpioNN</span> - Seer: ScorpioNN grabbed a pawn early, then created an advanced passer. Seer regained the pawn but gave a rook for a knight for the passer. Both engines created another passer, after some shuffling ScorpioNN captured the black passer on the 2nd rank. The game reached a RB vs BN position, ScorpioNN captured all the remaining black pawns, then mated after queening a pawn.</p><p><a href="https://tcec-chess.com/#div=l1&game=38&season=25">game 38</a>, <span style="background-color: #04ff00;">RubiChess</span> - Revenge: The were a few exchanges after the start, evals slowly increased after move 30. RubiChess opened the queen side and gave a rook for a bishop to create an advanced passer. in a QRB vs QRR position RubiChess gave up that passer and switched to another one on the king side. Revenge lost material but couldn't stop the passer, game over.</p><p><a href="https://tcec-chess.com/#div=l1&game=41&season=25">game 41</a>, <span style="background-color: #04ff00;">Clover</span> - rofChade: Queens were off early, all the rooks were on the a file with one black pawn between them. Clover moved a knight across the board to capture the pawn, with the king's help it managed to get the knight away safely. In a RBN vs RBB position Clover captured another pawn and queened a passer to win.</p><p><a href="https://tcec-chess.com/#div=l1&game=44&season=25">game 44</a>, <span style="background-color: #04ff00;">rofChade</span> - Caissa: Caissa blundered when its queen moved forward to grab a pawn, it saw the next sequence of moves in its PV but thought it was safe. rofChade immediately attacked the black king, the game reached a QR vs QR position with black two pawns up but its king completely exposed. Caissa had to give its queen for a rook, the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=l1&game=47&season=25">game 47</a>, <span style="background-color: #04ff00;">Revenge</span> - Seer: With all pieces on the board Revenge traded minors, gave a pawn and opened the g file. Some of Seer's pieces were too far to help defend the king, Seer had to trade RN for Q. The engines exchanged pieces and the game reached a Q vs BR position, Seer lost the bishop for a passer and was mated.</p><p><a href="https://tcec-chess.com/#div=l1&game=49&season=25">game 49</a>, <span style="background-color: #04ff00;">RubiChess</span> - Igel: Igel didn't castle its king, RubiChess opened files on the king side and center and threatened an attack with its major pieces. Igel exchanged pieces, the game reached a rook ending with white a pawn up. RubiChess had connected passers, Igel lost its rook for one, game over.</p><p><a href="https://tcec-chess.com/#div=l1&game=50&season=25">game 50</a>, <span style="background-color: #04ff00;">Seer</span> - Minic: Seer traded a knight for 3 pawns, then reduced to a RN vs RBN position and captured a 4th pawn. After exchanging knights Minic was left without pawns, eventually Minic lost the bishop for a passer and the game ended in a tablebase win. </p><p><a href="https://tcec-chess.com/#div=l1&game=54&season=25">game 54</a>, <span style="background-color: #04ff00;">DeepSjeng</span><span style="background-color: white;"> </span>- rofChade: DeepSjeng went a pawn up and exchanged cleared the center. The white bishop pair controlled many squares, after a long shuffle DeepSjeng captured another pawn and reduced to a RBB vs RBN position. DeepSjeng captured a third pawn and rofChade couldn't avoid a queening, it gave away its pieces and was mated.</p><p><a href="https://tcec-chess.com/#div=l1&game=58&season=25">game 58</a>, <span style="background-color: #04ff00;">Revenge</span> - Clover: Both engines castled long, then Revenge opened the a file. Revenge pushed a pawn to c6 and after exchanging queens moved both rooks to the a file. Clover captured pawns but had to give material to save its king. The game reached a RB vs B position with black 4 pawns up, Revenge captured pawns and queened its last one to win.</p><p><a href="https://tcec-chess.com/#div=l1&game=60&season=25">game 60</a>, <span style="background-color: #04ff00;">RubiChess</span> - Seer: Queens were off early and the black king moved without castling. RubiChess attacked through the center and created a passer. Seer walked its king to safety, after a while RubiChess started an exchange series where it gave up the passer and reduced to a BN vs R position. RubiChess created another passer, this time Seer couldn't prevent a queening and mate.</p><p><a href="https://tcec-chess.com/#div=l1&game=64&season=25">game 64</a>, <span style="background-color: #04ff00;">Caissa</span> - Revenge: After move 20 the engines exchanged pieces, Caissa went a pawn up and the game reached a RB vs RB position. The white king moved forward, after exchanging rooks Caissa captured another pawn and created a passer. Revenge blocked and captured the passer while Caissa captured the remaining black pawns to win.</p><p><i>Standings after RR1: RubiChess +6, Igel rofChade +2, Seer +1, Revenge Minic Caissa 0, Viridithas Clover -1, ScorpioNN -2, Fritz -3, DeepSjeng -4. RubiChess leads with a 2 point margin, it has won all games with the bias in white and drew against the bias in black. The fight for 2nd place is wide open, there were many decisive games and the reverse games may be significant. The 4 newcomer engines that started from the entrance league are not so strong in this league, this is probably their final appearance this season.</i></p><p><a href="https://tcec-chess.com/#div=l1&game=70&season=25">game 70</a>, <span style="background-color: #04ff00;">Caissa</span> - Minic: Caissa gave a pawn and opened the center, the black king did not castle and the black king side rook was trapped. In a QRN vs QRN position Minic freed its rook while Caissa captured two pawns, then exchanged queens. After a while Caissa captured a second pawn and then created a passer that Minic couldn't stop without losing a piece, game over.</p><p><a href="https://tcec-chess.com/#div=l1&game=71&season=25">game 71</a>, <span style="background-color: #04ff00;">Clover</span> - RubiChess: RubiChess was a pawn up while Clover attacked the uncastled black king. The game reached a RRN vs RRN position, Clover captured two pawns and created a passer. Progress was slow, after exchanging a pair of rooks Clover pushed the passer, after 30 moves it reached the 7th rank. Clover created a second passer and RubiChess couldn't stop both, Clover queened to win.</p><p><a href="https://tcec-chess.com/#div=l1&game=74&season=25">game 74</a>, <span style="background-color: #ffa400;">Seer</span> - <span style="background-color: white;">Clover</span>: Clover equalized though it was a down a rook for a bishop. The game was heading for a draw in a QRB vs QBB position when Seer didn't move on time and lost.</p><p><a href="https://tcec-chess.com/#div=l1&game=75&season=25">game 75</a>, <span style="background-color: #04ff00;">RubiChess</span> - Caissa: RubiChess gave two pawns and attacked the black king. It sacrificed a knight as well, and then regained the material in a series of exchanges and the game reached a RB vs RN position. Caissa gave a pawn to create a passer, the engines cleared the queen side pawns and exchanged minors. RubiChess blocked the black king away from the king side and pushed its pawns there, winning a rook ending with one pawn advantage.</p><p><a href="https://tcec-chess.com/#div=l1&game=83&season=25">game 83</a>, <span style="background-color: #04ff00;">Caissa</span> - <span style="background-color: #ffa400;">Seer</span>: The center was blocked and there were no exchanges after the start. After move 29 a few pawn exchanges created passers in the center for both engines, evals started to increase. The first piece exchange was queens on move 44 and the engines cleared the center pawns. Caissa doubled rooks on the h file, Seer gave a rook for a knight to avoid a trap for its king. In a RRB vs RBN Caissa captured pawns, then slowly improved its position. Then on move 80 Seer lost on time, though it was probably losing in any case.</p><p><a href="https://tcec-chess.com/#div=l1&game=84&season=25">game 84</a>, <span style="background-color: #04ff00;">Clover</span> - Viridithas: The engines gradually exchanged minor pieces, Clover captured a pawn and the game reached a QRB vs QRN position. After some shuffling Clover captured another pawn and a series of exchanges reduced to a B vs N ending. Clover queened a passer and then mated.</p><p><a href="https://tcec-chess.com/#div=l1&game=88&season=25">game 88</a>, <span style="background-color: #04ff00;">RubiChess</span> - rofChade: RubiChess threatened the black king, rofChade started a series of exchanges that resulted in a RNN vs RN position. It took a while but RubiChess managed to create a passer and promote to a queen, followed by mate.</p><p><a href="https://tcec-chess.com/#div=l1&game=94&season=25">game 94</a>, rofChade - <span style="background-color: #ffa400;">Seer</span>: Almost all pawns stayed on the board and the engines shuffled for a long time. Evals were close to 0 but there were too many pieces on the board for the draw rule, then Seer lost on time again.</p><p><a href="https://tcec-chess.com/#div=l1&game=96&season=25">game 96</a>, <span style="background-color: #04ff00;">Caissa</span> - Clover: There were almost no exchanges after the start and the engines mostly shuffled for a long time. Evals increased a little after move 45, Caissa pushed pawns and restricted the black pieces further. Caissa created a passer after a piece exchange, after more shuffling there were some more exchanges and only RB vs RN remained. Caissa had unstoppable passers, Clover lost material and was mated.</p><p><a href="https://tcec-chess.com/#div=l1&game=103&season=25">game 103</a>, <span style="background-color: #04ff00;">Igel</span> - Minic: Igel opened the king side, captured a pawn and created a passer. Minic exchanged pieces and regained the pawn, the game reached a RBN vs RBN position. The white king moved forward to support the passer, Igel captured a second pawn and Minic lost more material. The game ended in a tablebase win. </p><p><a href="https://tcec-chess.com/#div=l1&game=107&season=25">game 107</a>, <span style="background-color: #04ff00;">rofChade</span> - Clover: All the pawns were on the board, rofChade pushed its pawns and the black pieces had to retreat. Clover gave a bishop for two pawns, the engines exchanged pieces and pawns and the game reached a RN vs R position. Clover had two passers, onr was captured and the other blocked. eventually rofChade managed to exchange rooks, then queen a passer and mate.</p><p><a href="https://tcec-chess.com/#div=l1&game=109&season=25">game 109</a>, DeepSjeng - Igel: DeepSjeng seemed to be in control in a RB vs RR position with two advanced passers on the 6th and 7th ranks. However it didn't find the best moves and Igel managed to hold.</p><p><a href="https://tcec-chess.com/#div=l1&game=121&season=25">game 121</a>, <span style="background-color: #04ff00;">rofChade</span> - Igel: rofChade was up a pawn and evals slowly increased with no exchanges. The engines started exchanging pieces after move 33 and the game reached a QRR vs QRR position. The black king was in danger and Igel gave two pawns to get all pieces involved in the defense. rofChade exchanged a pair of rooks and pushed two passers forward, eventually Igel lost a rook to stop them, game over.</p><p><a href="https://tcec-chess.com/#div=l1&game=124&season=25">game 124</a>, <span style="background-color: #04ff00;">Clover</span> - Revenge: Clover controlled the open d file, it captured a pawn and created a passer on the queen side. Revenge gave a bishop for two pawns to expose the white king, but it ran out of checks after a while. Clover reduced to a RN vs R position, the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=l1&game=127&season=25">game 127</a>, <span style="background-color: #04ff00;">Igel</span> - Seer: There were no exchanges after the start, the first pawns were exchanged on move 20, the piece exchanged on move 29. Seer had a trapped bishop and evals increased steadily. Igel went two pawns up and reduced to a RB vs RB position, then it captured the trapped bishop. Igel queened a passer and mated.</p><p><a href="https://tcec-chess.com/#div=l1&game=129&season=25">game 129</a>, <span style="background-color: #04ff00;">Minic</span> - Clover: The engines opened files in the center and evals increased. Clover gave a rook for a bishop, the white king was exposed but after Minic exchanged queens its king was safe. The engines reduced to a RN vs BN position, Minic captured more pawns and the game ended in mate.</p><p><i>Standings after RR2: RubiChess +8, rofChade +6, Igel +5, Caissa +3, Clover +2, Minic +1, Seer Revenge 0, Viridithas -3, Fritz -6, ScorpioNN -7, DeepSjeng -9. RubiChess leads at the half way point, it lost its first game and drew two games with opening advantage. rofChade is in 2nd with Igel close behind, rofChade beat Igel in their direct game pair which could be important in a tiebreak situation. Caissa and Clover both improved their rank, they still have a small chance of advancing for the 3rd time this season. Seer crashed 3 times on time, it was losing against Caissa but it gifted wins in drawn positions to Clover and rofChade. I hope the qualification spots will not be decided by these crashes.</i></p><p><a href="https://tcec-chess.com/#div=l1&game=136&season=25">game 136</a>, <span style="background-color: #04ff00;">Minic</span> - Caissa: Minic was a pawn up, the engines exchanged minors and reached a QRR vs QRR position. Minic kept its queen and exchanged rooks, in a queen ending the engines traded pawns. Minic managed to capture all the black pawns and kept two to win.</p><p><a href="https://tcec-chess.com/#div=l1&game=137&season=25">game 137</a>, <span style="background-color: #04ff00;">RubiChess</span> - Clover: RubiChess was a pawn up, the engines cleared the queen side and RubiChess had a passer there. The engines gradually exchanged pieces and the game reached a B vs N ending. RubiChess pushed the passer to the 6th rank, then moved its king forward. Clover couldn't block the passer and keep the white king away, it lost its knight and the game.</p><p><a href="https://tcec-chess.com/#div=l1&game=143&season=25">game 143</a>, <span style="background-color: #04ff00;">rofChade</span> - Revenge: rofChade was a pawn up, it created a passer in the center. rofChade gave a bishop and attacked through the center, Revenge gave back a knight to keep its king safe. More pieces were exchanged, Revenge captured the passer but rofChade captured pawns and the game reached a rook ending with enough advantage to win.</p><p><a href="https://tcec-chess.com/#div=l1&game=145&season=25">game 145</a>, Fritz - <span style="background-color: #04ff00;">Igel</span>: Fritz had a passer on the 6th rank but wasn'r strong enough to push it forward, Igel's eval dropped to 0. When Fritz pushed another pawn Igel saw an opening to attack the exposed white king. It gave a pawn and risked facing 3 connected passers, Fritz realized its mistake too late. Igel used checks to capture the white passers and reduce to a RB vs RN position 2 pawns up. This was enough to later queen a passer and win.</p><p><a href="https://tcec-chess.com/#div=l1&game=151&season=25">game 151</a>, <span style="background-color: #04ff00;">Igel</span> - Clover: The engines exchanged a few minor pieces, most pawns remained on the board. After some shuffling the engines opened files on the queen side. Igel threatened pieces with pins and forks in the center, the tension was released in a series of exchanges that left a RN vs BN position. Igel captured two pawns to win.</p><p><a href="https://tcec-chess.com/#div=l1&game=160&season=25">game 160</a>, <span style="background-color: #04ff00;">Seer</span> - rofChade: The black king moved without castling, and the king side rook could only develop through the h file. Seer captured a pawn and created an advanced passer in the center. rofChade shuffled while Seer walked its king to the queen side, then a series of exchanges reduced to a RBN vs RBB position with white two pawns up. rofChade captured the passer but Seer captured all remaining black pawns and was 5 pawns up, it pushed its pawns forward to win.</p><p><a href="https://tcec-chess.com/#div=l1&game=164&season=25">game 164</a>, <span style="background-color: #04ff00;">DeepSjeng</span> - Clover: There were almost no exchanges after the start, a pawn exchange opened the g file. DeepSjeng castled long and moved its pieces to the king side, then switched to the queen side when both engines created passers there. DeepSjeng captured a rook for a knight and hid its king behind a black passer. The engines exchanged queens after the black king was threatened, then DeepSjeng captured a rook for its passer, followed by mate.</p><p><a href="https://tcec-chess.com/#div=l1&game=168&season=25">game 168</a>, <span style="background-color: #04ff00;">Revenge</span> - Minic: Revenge pushed a pawn to h6 and castled long. The black queen moved forward and captured two pawns but the black king was stuck in the center surrounded by open files. Revenge gave a rook and attacked with all its pieces, Minic couldn't find a safe spot for its king and it lost the queen by a fork. The game reached a QBN vs RRB position, Revenge continued to chase the black king and forced mate.</p><p><a href="https://tcec-chess.com/#div=l1&game=176&season=25">game 176</a>, <span style="background-color: #04ff00;">rofChade</span> - Caissa: A series of exchanged left a QR vs QR position. rofChade had an advanced passer in the center that Caissa blocked. It took rofChade 25 moves to push the passer to the 7th rank and 10 more moves to reduce to a king and pawns ending. Caissa captured the passer, material was equal but the white king was better placed to ensure the win.</p><p><a href="https://tcec-chess.com/#div=l1&game=181&season=25">game 181</a>, <span style="background-color: #04ff00;">RubiChess</span> - Igel: After the start RubiChess had a bishop pair advantage and an advanced passer in the center. In a QRB vs QRN position RubiChess pushed the passer to the 7th rank and Igel couldn't get rid of it. The engines exchanged queens, RubiChess created a second passer, Igel captured one but the other promoted to a queen. RubiChess lost the rook but had enough material to win.</p><p><a href="https://tcec-chess.com/#div=l1&game=189&season=25">game 189</a>, <span style="background-color: #04ff00;">Fritz</span> - Caissa: The black king moved without castling, trapping the king side rook. The engines gradually exchanged pieces until only RBN vs RBN were left, Fritz went a pawn up and created two passers. After exchanging bishops Caissa captured one passer, it lost the knight for the other. It took Fritz another 17 moves to reach a tablebase win.</p><p><a href="https://tcec-chess.com/#div=l1&game=190&season=25">game 190</a>, <span style="background-color: #04ff00;">Revenge</span> - Clover: There were many exchanges after the start and the game reached a QRN vs QRN position. Clover had two isolated pawns, after exchanging queens Revenge captured one. Revenge had a rook on the 7th rank, the white king moved forward, Clover lost material and was mated.</p><p><a href="https://tcec-chess.com/#div=l1&game=196&season=25">game 196</a>, <span style="background-color: #04ff00;">Caissa</span> - Revenge: The engines opened the king side, Revenge gave a knight for a pawn to gain a development advantage. However, Caissa managed to develop its pieces and in a series of exchanges reduced to a RBN vs RB position. Revenge pushed a passer forward and Caissa gave a bishop to stop it, by then Caissa was two pawns up. The white king moved forward and captured the last black pawn, the game ended in a tablebase win. </p><p><i>Standings after RR3: RubiChess +14, rofChade +9, Igel +8, Caissa +4, Revenge Seer +1, Clover -1, Minic -2, Viridithas -5, Fritz -8, ScorpioNN -9, DeepSjeng -12. RubiChess increased the lead after another RR with 6 white wins and no loss. rofChade has an advantage in the race for 2nd place over Igel, though anything can happen. Caissa is probably too far behind to have a chance to advance. Clover dropped after a poor RR with 4 losses and one win. Seer climbed a little, it had no crashes in the RR.</i></p><p><a href="https://tcec-chess.com/#div=l1&game=207&season=25">game 207</a>, <span style="background-color: #04ff00;">RubiChess</span> - Caissa: The center was blocked and the c file was open, there were only a few exchanges after the start. Caissa walked its king to the queen side, it was without pawn support but not under attack. The game reached a RNN vs RNN position, after move 40 evals slowly increased. RubiChess captured a pawn, aftr exchanging a pair of knights RubiChess created 2 connected passers. Caissa regained the pawn and captured one of the passers, rooks were exchanged leaving a knight ending. The white king was much closer to the pawns, RubiChess captured the remaining black pawns to win.</p><p><a href="https://tcec-chess.com/#div=l1&game=209&season=25">game 209</a>, <span style="background-color: #04ff00;">Revenge</span> - rofChade: Revenge was a pawn up, the engines opened the king side, rofChade castled long but Revenge castled short. rofChade tried to attack the white king, but was not strong enough after exchanging queens. Revenge captured another pawn and lost a knight temporarily, a series of exchanges reduced to a RBN vs RBN position with white a pawn up. Revenge had a passer, it avoided exchanging rooks until it captured another pawn. The white king came forward and Revenge captured the last black pawn. The game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=l1&game=218&season=25">game 218</a>, <span style="background-color: #04ff00;">Viridithas</span> - Caissa: Viridithas pushed pawns and opened the king side. The white king walked to the queen side without castling, Viridithas doubled its rooks on the h file. The game reached a QRR vs QRR position and Viridithas attacked the back rank. Caissa tried to protect its king, it lost first one pawns then another and Viridithas reduced to a winning king and pawns ending.</p><p><a href="https://tcec-chess.com/#div=l1&game=223&season=25">game 223</a>, <span style="background-color: #04ff00;">Igel</span> - Revenge: Most of the action after the start was on the queen side, both engines created a passer there. Igel gave two pawns, letting Revenge have 3 passers but exposing the black king to attack. Igel captured pawns and the game reached a RRB vs RRN position with white a pawn up. Revenge lost a piece for a white passer, Igel had enough advantage that it gave its bishop to reduce to a winning 7-man rook ending. It took another 35 moves to adjudicate the game.</p><p><a href="https://tcec-chess.com/#div=l1&game=231&season=25">game 231</a>, <span style="background-color: #04ff00;">Viridithas</span> - rofChade: Both engines didn't castle their king, there were only a few exchanges after the start and the engines mostly played behind their pawn lines. After opening the king side and exchanging a pair of rooks Viridithas gave 2 pawns and captured a bishop. In a RBN vs RN position Viridithas captured 3 pawns and pushed passers forward. rofChade couldn't avoid a queening, game over.</p><p><i>Standings with 5 round to go: RubiChess +16, Igel +11, rofChade +9, Seer +4, Caissa +3, Revenge +1, Clover 0, Minic -1, Viridithas -4, Fritz ScorpioNN -12, DeepSjeng -15. Drama in the fight for 2nd place. Igel won 3 games in white against lower ranked engines, and rofChade lost twice in black. Igel is leading rofChade by a point with 5 games to play, it still has to play black against rofChade and rofChade has a tiebreak advantage.</i></p><p><a href="https://tcec-chess.com/#div=l1&game=235&season=25">game 235</a>, <span style="background-color: #04ff00;">Igel</span> - Minic: Minic was a pawn up and Igel had a bishop pair advantage. The engines cleared the queen side pawns and shuffled for a while, evals were mostly stable until move 45. Igel regained the pawn and reduced to a RBB vs RBN position. Minic may have held longer but it was inaccurate in time pressure, Igel threatened mate and Minic had to give a rook for a bishop. The game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=l1&game=247&season=25">game 247</a>, <span style="background-color: #04ff00;">Igel</span> - RubiChess: RubiChess pushed the g pawn and Igel moved a bishop to h6, disrupting the black king's castling. The engines opened the king side, RubiChess captured two pawns and the white king was exposed. RubiChess gave a rook for a bishop and blocked the g file, then it castled long and the game reached a QRR vs QRN position. Igel moved its pieces forward, RubiChess delayed with checks but eventually Igel reduced to a R vs N ending. Igel captured pawns, then queened a passer and mated.</p><p><a href="https://tcec-chess.com/#div=l1&game=250&season=25">game 250</a>, Fritz - <span style="background-color: #04ff00;">Clover</span>: Fritz was a pawn up with eval advantage but Clover seemed to equalize. Clover gave a bishop for two pawns and exposed the white king. On move 42 Fritz blundered twice, it saw Clover's response in its PV but realized the mistake only after Clover moved. Clover used an attack on the white king to capture the white queen and reduce to a QN vs RRB position with black two pawns up. Fritz couldn't defend against the rushing passers and the attacks on its king, it lost pieces and the game ended in a tablebase win.</p><p><i>Standings with 2 rounds to go: RubiChess +16, Igel +13, rofChade +10, Seer +4, Caissa Clover +2, Revenge +1, Minic Viridithas -3, ScorpioNN -12, Fritz -14, DeepSjeng -16. Igel increased the gap to rofChade to 1.5 points. rofChade only drew as white against Clover while Igel beat RubiChess as white. With two games to play this is a substantial advantage for Igel, though it still has to face rofChade as black.</i></p><p><a href="https://tcec-chess.com/#div=l1&game=253&season=25">game 253</a>, <span style="background-color: #04ff00;">rofChade</span> - Igel: rofChade castled long and pushed pawns on the king side, placing a pawn on h6. Evals started to increase after the center was opened, Igel pushed pawns on the queen side, rofChade went a pawn up and created connected passers. rofChade gave back the pawn to bring a passer to the 7th rank. In a RB vs RB position rofChade pushed a second pawn forward, Igel lost material and was mated.</p><p><i>With this win rofChade is only 0.5 points behind Igel in 2nd place. In the last round rofChade plays as black and Igel as white so Igel still has an advantage. In case of a tie rofChade will advance.</i></p><p><i>The Igel - Seer game 259 didn't start properly and had to be restarted. As a result the game was played last, after the ScorpioNN - rofChade which was supposed to be last according to the schedule.</i></p><p><i>rofChade held a draw against ScorpioNN as black. Igel needs a draw to finish in 2nd place.</i></p><p><a href="https://tcec-chess.com/#div=l1&game=259&season=25">game 259</a>, <span style="background-color: #04ff00;">Igel</span> - Seer: Igel captured the h pawn and exposed the black king to attack. The white d pawn became a passer, the game reached a QRN vs QRN position. After exchanging queens Igel captured all the black pawns and was 5 pawns up. Seer tried to avoid a 7-man tablebase loss but it couldn't avoid a queening and mate.</p><p><i>Igel secures 2nd place with this win, rofChade finished 3rd.</i></p></div>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com0tag:blogger.com,1999:blog-4430065842059358622.post-21760867687153891872023-08-24T22:58:00.000+03:002023-08-24T22:58:17.641+03:00Season 25 league 2 statistics<p>A summary <a href="https://drive.google.com/open?id=1dpikbAHWxz1wLcsOzG0kxKCk0Hn67IYJPL8B1wzj_rk" target="_blank">statistics table</a> of previous stages and seasons. </p><p><b>Draw rate, wins</b></p><p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhdvIpKxYU7EuquQiwccDxruYHPbbK5_ZIq-D1LOi6Dj7nVzekY4BpcC6FDpni5dpBthHvOpk_igVugi7dOqKJ44tvTCfr98MRwCHvXJTi520pS3KF4D1oiHKg6ZhyVm3zab-egzFD2i8JheKrWfrVfwEWgQF6aC9Phw8FI70DPMZjvT7FdSbtFpiR1r6s/s480/S25.l2.g1.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhdvIpKxYU7EuquQiwccDxruYHPbbK5_ZIq-D1LOi6Dj7nVzekY4BpcC6FDpni5dpBthHvOpk_igVugi7dOqKJ44tvTCfr98MRwCHvXJTi520pS3KF4D1oiHKg6ZhyVm3zab-egzFD2i8JheKrWfrVfwEWgQF6aC9Phw8FI70DPMZjvT7FdSbtFpiR1r6s/s320/S25.l2.g1.jpg" width="320" /></a></div><p>Final draw rate was 63.2%. </p><p><b>Game termination</b><br /><br />The three most common game termination causes were:<br />49.2% - TCEC draw rule<br />23.1% - SyzygyTB<br />17.4% - Mate<br /><br />There were no crashes in the stage.<br /></p><p><b>Moves per game</b></p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgPsXaemX_2n-GwLMdLIK7tawVWBJg8oZ70oUmHOxtoTvzAoLBe_W3eKuwJwFtXWUvhvjhdcQgHTHYI2fJW2EGjpp_vD5Dm5vZt6uLN_l43Kb_TEpcr0ge_hJ1qwCkGB04Kpv4l5lhzJuczvqX3sZWzLJSjmExsjxga3w3UQTG03yXARSV2z0DpqEhImzs/s480/S25.l2.g2.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgPsXaemX_2n-GwLMdLIK7tawVWBJg8oZ70oUmHOxtoTvzAoLBe_W3eKuwJwFtXWUvhvjhdcQgHTHYI2fJW2EGjpp_vD5Dm5vZt6uLN_l43Kb_TEpcr0ge_hJ1qwCkGB04Kpv4l5lhzJuczvqX3sZWzLJSjmExsjxga3w3UQTG03yXARSV2z0DpqEhImzs/s320/S25.l2.g2.jpg" width="320" /></a></p><p>Median= 63<br />Average= 69.7<br /><br />There were 32 games longer than 100 moves, the longest was 175 moves (Velvet - Caissa, game 9, draw). <br /><br /><b>Time per game (hours)</b></p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEicWGMtyUxy0QDNXqyJ0WxmH-E_p5mpW_4KwKXPnJlq1dxCGQvsPXncavconjgwy2p9g5eVt4DtZrjU5vCcEuLZTPji_EZRDT7S0ZCna0wTW6Sa_cwbQSCxGrbAmNH4HuOGH60jw7oZblGKugW94_3PZsr4Sxk9m9Uuges_IsASoLrfw92CAL0BhkhHGr8/s480/S25.l2.g3.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEicWGMtyUxy0QDNXqyJ0WxmH-E_p5mpW_4KwKXPnJlq1dxCGQvsPXncavconjgwy2p9g5eVt4DtZrjU5vCcEuLZTPji_EZRDT7S0ZCna0wTW6Sa_cwbQSCxGrbAmNH4HuOGH60jw7oZblGKugW94_3PZsr4Sxk9m9Uuges_IsASoLrfw92CAL0BhkhHGr8/s320/S25.l2.g3.jpg" width="320" /></a></p><p>Median= 1:01<br />Average= 1:00<br /><br /><b>Openings</b><br /><br />There were variable length book openings in this stage. The first letter of the ECO codes was distributed as follows: </p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg988T8Q8TY_L_JA81neC5whhn7nkgG6ZHsVgHr8dGBzll7Zw4noajqqPx46DX8iuwpS-AnNGGM3CqqhjvNcNNDkfOMjC2kMJ6M9VP52ndtgXJCSgbCBA5RFKQXRzbILWEG05Jo2sqFy9-e-HfyBM5JPKJj16gJla0VvwEaJc2lIWOhDIly1oaVPeBW30c/s480/S25.l2.g4.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg988T8Q8TY_L_JA81neC5whhn7nkgG6ZHsVgHr8dGBzll7Zw4noajqqPx46DX8iuwpS-AnNGGM3CqqhjvNcNNDkfOMjC2kMJ6M9VP52ndtgXJCSgbCBA5RFKQXRzbILWEG05Jo2sqFy9-e-HfyBM5JPKJj16gJla0VvwEaJc2lIWOhDIly1oaVPeBW30c/s320/S25.l2.g4.jpg" width="320" /></a></p><p>The engines had little freedom to choose the opening variant, 94.7% of the game pairs repeated the same ECO code and 90.1% repeated the opening variant twice. Only in 1.5% of the game pairs the first letter of the ECO code was not repeated.<br /></p><p><b>Reverse pairs, wins</b></p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgUGWjPtLi6hXmwF_Fiyln5rLhkI-ohhNErVpjJp3krhSFrS_l720FlPYhY0BZ9gneDczZUX1iC5-jN4SBtUXHhYHNdCQsqyJY9kTcvfz4lZCL3LMd_pSCFuXANso2ecPFwXjnZDSp25-1FT4CEhE3eLxpwON1A3e8zU56BF7V5dKxsxWMsQDt0wBCxwOU/s480/S25.l2.g5.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgUGWjPtLi6hXmwF_Fiyln5rLhkI-ohhNErVpjJp3krhSFrS_l720FlPYhY0BZ9gneDczZUX1iC5-jN4SBtUXHhYHNdCQsqyJY9kTcvfz4lZCL3LMd_pSCFuXANso2ecPFwXjnZDSp25-1FT4CEhE3eLxpwON1A3e8zU56BF7V5dKxsxWMsQDt0wBCxwOU/s320/S25.l2.g5.jpg" width="320" /></a></p><p><b>Reverse pairs, same moves</b></p><div><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhlYixn_u93Sv5e6Laet_63R3_PYYLy4pAulTt7vK71Ugb7gy_n1udXGkA3Yc58veg0GFhpWb0HBULwd8NmG6uKyLy0zsRGHFomcSQWUwceMCjEr35lyMdCMju0QAC9-nD6hebIhckV-_r4yxYtAUUweiStDXa8P5AzgD62e58bCQtSNaL7pS9RS_LagJY/s480/S25.l2.g6.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhlYixn_u93Sv5e6Laet_63R3_PYYLy4pAulTt7vK71Ugb7gy_n1udXGkA3Yc58veg0GFhpWb0HBULwd8NmG6uKyLy0zsRGHFomcSQWUwceMCjEr35lyMdCMju0QAC9-nD6hebIhckV-_r4yxYtAUUweiStDXa8P5AzgD62e58bCQtSNaL7pS9RS_LagJY/s320/S25.l2.g6.jpg" width="320" /></a> </p><p>Pairs of reverse games diverged less quickly than usual, 14.4% diverged immediately out of book, 51.5% of the pairs diverged at most after 1 move. The longest repeated sequence of moves was 44 (!) plys (DeepSjeng - Caissa, games 62 and 128, Sicilian Najdorf, Polugayevsky variation, two draws) </p><p><br /></p></div>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com0tag:blogger.com,1999:blog-4430065842059358622.post-81446823397551607052023-08-16T01:13:00.025+03:002023-08-25T01:11:57.441+03:00Season 25 league 2<p><b>Final standings</b></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiCGF5xsK5sHeCIGGR-fyvy41arwvgG3jIi1RwxOnn6s7cmqcPKqbcqUUvaK8nGUaBjpbf5zSt9iBWCxjHUcBC2mNGOVURRzefs4K2U5aMxoZySefqjon_012kyiNOk_mMjS6EorD4_aJvfXu9kbs6nA84xC9hfYFJxwS1SgFeqKDMW-Q-qxpgF6MLbJQw/s975/tab1.png" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="975" data-original-width="628" height="640" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiCGF5xsK5sHeCIGGR-fyvy41arwvgG3jIi1RwxOnn6s7cmqcPKqbcqUUvaK8nGUaBjpbf5zSt9iBWCxjHUcBC2mNGOVURRzefs4K2U5aMxoZySefqjon_012kyiNOk_mMjS6EorD4_aJvfXu9kbs6nA84xC9hfYFJxwS1SgFeqKDMW-Q-qxpgF6MLbJQw/w413-h640/tab1.png" width="413" /></a></div><br /><p>Clover, Caissa, Viridithas and DeepSjeng advance to league 1. The 4 qualifiers from the entrance league continue their journey in season 25, all advance for a second time. These engines led the league from the start, together with Arasan. At the half way point Arasan was in 4th place and DeepSjeng trailing by a point. In RR3 Clover, Caissa and Viridithas extended their lead while DeepSjeng and Arasan continued to battle for 4th place. Two rounds to go DeepSjeng and Arasan were tied, but then DeepSjeng beat Arasan in their only decisive game and this was enough to secure the qualification spot.</p><p>When the league started Arasan lost a few games in the first rounds against engines that were supposed to be weaker. It turned out that Arasan was run using wrong settings, this was fixed and its first few games were rerun.</p><p>The 4 qualifiers will play in league 1 together with:<br />played in season 24 league 1 - Igel, Revenge, RubiChess, rofChade, ScorpioNN, Seer, Minic, Fritz </p><p><b>Interesting games</b></p><p><a href="https://tcec-chess.com/#div=l2&game=1&season=25">game 1</a>, <span style="background-color: #04ff00;">Viridithas</span> - BlackMarlin: The game reached a RB vs RB position with white a pawn up and each engine with one passer. The engines shuffled for a long time, then BlackMarlin played inaccurately and evals increased. Viridithas captured the black passer, BlackMarlin lost its rook for the white passer, game over. </p><p><a href="https://tcec-chess.com/#div=l2&game=3&season=25">game 3</a>, <span style="background-color: #04ff00;">Clover</span> - Halogen: Clover had a pawn majority on the queen side that later became a passer. Clover created a second passer with a piece exchange. In a QRB vs QRN position Clover created a third passer and pushed all three to the 7th rank. Halogen lost two pieces for the passers, and the game ended in a tablebase win. </p><p><a href="https://tcec-chess.com/#div=l2&game=4&season=25">game 4</a>, <span style="background-color: #04ff00;">Arasan</span> - <span style="background-color: white;">Velvet</span>: Velvet had a passive bishop stuck on the king side, the engines opened the queen side and evals increased steadily. Arasan captured a pawn and created a passer in a QBN vs QBN position. Arasan threatened the black king, it gave the knight and captured 3 more pawns. Velvet lost its bishop and couldn't stop all the passers, Arasan queened and mated.</p><p><a href="https://tcec-chess.com/#div=l2&game=5&season=25">game 5</a>, <span style="background-color: #04ff00;">Caissa</span> - Marvin: The queen side was blocked, Caissa gave a pawn and created a passer in the center. The white king walked to the queen side and Caissa attacked on the king side. The engines exchanged pieces and the game reached a double rook ending with white a pawn up. Caissa had connected passers, Marvin lost material to stop them and was mated.</p><p><a href="https://tcec-chess.com/#div=l2&game=12&season=25">game 12</a>, <span style="background-color: #04ff00;">Viridithas</span> - Uralochka: Viridithas castled long and opened the king side. Uralochka attacked on the queen side and gave two minors for a rook, in a series of exchanges the engines reduced to a QRN vs QR position with black 4 pawns up. Viridithas captured 3 pawns back and pushed a passer to win. </p><p><a href="https://tcec-chess.com/#div=l2&game=15&season=25">game 15</a>, <span style="background-color: #04ff00;">Arasan</span> - Tucano: Arasan gave a knight for 3 pawns and created connected passers. Tucano captured a rook for a bishop and tried to block the passers, Arasan captured another pawn and created another passer. Tucano captured one passer but lost material and eventually was mated.</p><p><a href="https://tcec-chess.com/#div=l2&game=19&season=25">game 19</a>, <span style="background-color: #04ff00;">BlackMarlin</span> - Marvin: Marvin was up a pawn but its king moved without castling. The game reached a QR vs QR position and the black rook was stuck on the queen side. By the time Marvin freed its rook BlackMarlin captured pawns and reduced to a rook ending with connected passers. Marvin tried to block the passers with its king and was mated.<br /></p><p><a href="https://tcec-chess.com/#div=l2&game=23&season=25">game 23</a>, <span style="background-color: #04ff00;">Viridithas</span> - Arasan: Arasan was a pawn up but its king moved without castling. Queens were off and Viridithas captured a rook for a bishop, leading to a RRB vs RBN position. After exchanging a pair of rooks the engines captured pawns until there was only one left per engine. Arasan tried to block the white passer but lost its bishop, Viridithas queened and won.</p><p><a href="https://tcec-chess.com/#div=l2&game=25&season=25">game 25</a>, <span style="background-color: #04ff00;">Clover</span> - BlackMarlin: The king side opened and Clover castled long. BlackMarlin protected its king and the engines exchanged pieces until only QRN vs QRB remained. Clover was a pawn up with a passer, the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=l2&game=26&season=25">game 26</a>, <span style="background-color: #04ff00;">Arasan</span> - Uralochka: Uralochka was a pawn up early, the engines gradually exchanged pieces until only RB vs RN remained. Arasan used a pin on the back rank to capture pawns, then queened a passer to win.</p><p><a href="https://tcec-chess.com/#div=l2&game=27&season=25">game 27</a>, <span style="background-color: #04ff00;">Caissa</span> - Viridithas: Queens were off early, after a while Caissa captured a pawn. The engines shuffled a long time in a closed position, then exchanged pieces until reaching a rook ending. Caissa captured more pawns and queened a passer to win.</p><p><a href="https://tcec-chess.com/#div=l2&game=29&season=25">game 29</a>, <span style="background-color: #04ff00;">DeepSjeng</span> - Halogen: The engines shuffled in a QRN vs QRN position, then DeepSjeng captured a pawn. Halogen exchanged queens and pushed a passer but DeepSjeng captured it. Halogen lost the bishop to avoid mate, it took DeepSjeng 35 more moves to convert the win.</p><p><a href="https://tcec-chess.com/#div=l2&game=36&season=25">game 36</a>, <span style="background-color: #04ff00;">Clover</span> - Arasan: Arasan gave a rook and two pawns for a bishop early, putting a knight on d3 and forcing the white king to move. However this did not compensate for the material after Clover moved its king to safety. Clover gave back a rook for a bishop and reduced to a RB vs RN position with 3 pawns up. Arasan couldn't stop the white passers, game over. </p><p><a href="https://tcec-chess.com/#div=l2&game=38&season=25">game 38</a>, Caissa - <span style="background-color: #04ff00;">Clover</span>: Clover was up a pawn from the opening. The queen side was blocked and Clover created a passer in the center. There was a lot of shuffling, Clover moved its major pieces to the king side and threatened the black king. Clover moved its king to the center, then used a mate threat to capture all the black pawns on the queen side. It was 5 pawns up, it exchanged pieces and gained more material, the game ended in mate.</p><p><a href="https://tcec-chess.com/#div=l2&game=40&season=25">game 40</a>, <span style="background-color: #04ff00;">DeepSjeng</span> - Viridithas: Evals started to increase after move 30. DeepSjeng attacked the king side and in a series of exchanges reduced to a RBB vs RB position with black two pawns up. The white bishop pair was strong, Viridithas gave up material and was mated quickly.</p><p><a href="https://tcec-chess.com/#div=l2&game=51&season=25">game 51</a>, <span style="background-color: #04ff00;">DeepSjeng</span> - Clover: DeepSjeng captured a passer on the queen side, then gave it back to create an advanced passer in the center. Clover gave a rook for a knight to get rid of the passer, the game reached a RBB vs BNN position with black two pawns up. The black pawns were isolated and DeepSjeng captured all of them. Clover tried to stop the last white pawn, it lost material and the game ended in a tablebase win.</p><p><i>Standings after RR1: Clover +5, DeepSjeng +3, Viridithas +2, Caissa Arasan +1, BlackMarlin Halogen Tucano -1, Marvin Uralochka Velvet -2, Wasp -3. There are 5 engines competing for the the 4 qualifying spots. These are the 4 newcomers that advanced from the entrance league, and Arasan that is trying to take one spot from them. The current standings may be biased by the openings, the picture will be clearer after RR2 and the reverse games.</i></p><p><a href="https://tcec-chess.com/#div=l2&game=70&season=25">game 70</a>, <span style="background-color: #04ff00;">Velvet</span> - Arasan: The engines opened a few files and exchanged all rooks. The black queen moved forward and was almost trapped, Arasan gave a knight pawns to help the queen escape. In a QBN vs QN position Velvet gave a third pawn and created a passer. After exchanging queens Arasan couldn't prevent a queening, game over.</p><p><a href="https://tcec-chess.com/#div=l2&game=71&season=25">game 71</a>, Marvin - <span style="background-color: #04ff00;">Caissa</span>: Marvin had an advantage from the opening, there were no exchanges and evals came down. Marvin gave a rook for a knight and pawn to open the king side and attack. Caissa defended its king and evals turned negative. Marvin gave a rook and tried to keep the attack alive, Caissa gave a rook for a bishop while Marvin captured pawns. The game reached a RB vs B with white 3 pawns up, the white passers were not strong enough and Caissa mated.</p><p><a href="https://tcec-chess.com/#div=l2&game=89&season=25">game 89</a>, <span style="background-color: #04ff00;">Arasan</span> - Viridithas: Viridithas was up a pawn but its king moved without castling. The game reached a RRB vs RRB position, Arasan regained the pawn and created a passer. Arasan then gave a rook for a bishop and pawn and reduced to a B vs R ending. The white passer was fast, Viridithas moved its king to block it while Arasan connected a second passer. Viridithas managed to stop the passers but the king and pawns position left was a win for Arasan.</p><p><a href="https://tcec-chess.com/#div=l2&game=91&season=25">game 91</a>, BlackMarlin - <span style="background-color: #04ff00;">Clover</span>: BlackMarlin had an advantage from the opening and was a pawn up. After a long shuffle the center opened, BlackMarlin gave a rook and knight to queen a passer. In an unusual imbalance with 3 queens on the board BlackMarlin was not accurate enough, its king and queens were targets for Clover. BlackMarlin tried to push pawns, Clover captured them and went 2 pawns up. The white pieces were pushed back around the king and eventually Clover captured a queen for a rook. Clover captured another piece and then chased the white king and mated.</p><p><a href="https://tcec-chess.com/#div=l2&game=102&season=25">game 102</a>, <span style="background-color: #04ff00;">Arasan</span> - Clover: Clover was a pawn up but its king moved without castling. Clover managed to develop its king side rook, most pieces moved to the queen side. Arasan had a strong bishop pair, while the two black knights were more passive. Arasan captured two pawns and the game reached a RBB vs RNN position. Arasan slowly pushed a passer forward, Clover lost its rook to stop it. The game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=l2&game=106&season=25">game 106</a>, <span style="background-color: #04ff00;">Viridithas</span> - DeepSjeng: Viridithas pushed a pawn to f6 and trapped a black bishop in the corner. After some preparation Viridithas gave a pawn and opened the king side, DeepSjeng freed its bishop but the black king was in danger. DeepSjeng traded its queen for a rook and a bishop, reducing to a QR vs RRB position. Viridithas increased the pressure, gained material and won.</p><p><a href="https://tcec-chess.com/#div=l2&game=114&season=25">game 114</a>, <span style="background-color: #04ff00;">Caissa</span> - Arasan: There were many early exchanges and the game reached a RB vs RB position with white a pawn up. After exchanging bishops it took Caissa 20 moves to capture another pawn. It slowly pushed a passer forward to win.</p><p><i>Standings after RR2: Clover +7, Caissa +6, Viridithas +5, Arasan +4, DeepSjeng +2, BlackMarlin -1, Velvet Uralochka -2, Wasp Tucano -4, Marvin -5, Halogen -6. Caissa had an excellent RR2 with 5 wins, it jumped to 2nd place. The 4 leaders each has one game pair loss, DeepSjeng in 5th has none but it only has one game pair win against the lower ranked engines.</i></p><p><a href="https://tcec-chess.com/#div=l2&game=146&season=25">game 146</a>, <span style="background-color: #04ff00;">Clover</span> - Viridithas: The engines mostly shuffled for a long time with all pawns on the board. The first pawn exchange was on move 79, on move 98 the engines opened the center and the game reached a QR vs QN position with black a pawn up. After exchanging queens Clover moved its king forward, it captured most of the black pawns and the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=l2&game=155&season=25">game 155</a>, <span style="background-color: #04ff00;">Viridithas</span> - Arasan: The black king was stuck in the center and under attack, Arasan gave a rook for a bishop to stay alive. Arasan tried to counter, it gave a knight for two pawns and attacked but Viridithas moved its king to safety. In a RRN vs RB position Viridithas kept one pawn and captured black ones gradually, the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=l2&game=168&season=25">game 168</a>, <span style="background-color: #04ff00;">Clover</span> - Arasan: Clover was a minor piece up but its queen side pieces were not developed. Arasan played inaccurately, it gave pawns and tried to attack through the center but Clover kept its king safe and developed its pieces. The engines exchanged pieces until only RBN vs RB remained, Arasan gave up material and was mated.</p><p><a href="https://tcec-chess.com/#div=l2&game=194&season=25">game 194</a>, DeepSjeng - <span style="background-color: #04ff00;">Caissa</span>: Caissa had an eval advantage from the opening, material was equal and the engines gradually exchanged pieces, the game reached a double knight ending with black a pawn up. After sone shuffling the engines exchanged a pair of knights, then DeepSjeng allowed the remaining knights to be exchanged and regained the pawn. This was a bad idea since Caissa had a passer, the white king could not defend both sides of the board and the game ended in a tablebase win.</p><p><i>Standings after RR3: Clover +11, Caissa Viridithas +10, DeepSjeng +5, Arasan +3, BlackMarlin 0, Uralochka Velvet -3, Wasp -5, Marvin -7, Tucano -9, Halogen -12. The 3 leaders are going to qualify, the final order is not decided yet. The 4th qualification spot is still a race between DeepSjeng and Arasan. DeepSjeng had a good RR3 with 4 wins against lower ranked engines, Arasan had only 1 and it has to be better in RR4 to have a chance.</i></p><p><a href="https://tcec-chess.com/#div=l2&game=199&season=25">game 199</a>, <span style="background-color: #04ff00;">BlackMarlin</span> - Viridithas: Evals increased from the start in a closed position with equal material. BlackMarlin opened the queen side and threatened the black king, then moved a rook forward on the king side. After some shuffling Viridithas exchanged queens to get its king to the center, the game reached a BN vs BN position with white two pawns up. Viridithas lost a bishop but couldn't stop a white passer, BlackMarlin queened and mated.</p><p><a href="https://tcec-chess.com/#div=l2&game=201&season=25">game 201</a>, Halogen - <span style="background-color: #04ff00;">Clover</span>: Halogen started with an eval advantage but Clover managed to equalize. Halogen was not careful, itlet Clover open the queen side and reduce to a RRN vs RRB position. Material was equal but Clover had connected passers it pushed forward and Halogen couldn't stop. Clover gave some material and queened one passer, then slowly converted the QB vs RR ending. </p><p><a href="https://tcec-chess.com/#div=l2&game=221&season=25">game 221</a>, <span style="background-color: #04ff00;">Arasan</span> - Viridithas: Arasan had an eval advantage and more space, the engines exchanged most minor pieces. Arasan opened a file on the king side and gave a pawn while it threatened the black king. In a QRR vs QRR position Arasan moved its queen to the center and the black king had to leave the corner. After exchanging a pair of rooks Arasan moved its rook to the 7th rank, Viridithas gave its queen to get rid of it. Arasan queened a passer to win.</p><p><a href="https://tcec-chess.com/#div=l2&game=234&season=25">game 234</a>, <span style="background-color: #04ff00;">Arasan</span> - Clover: Arasan had an eval advantage from the start, the engines gradually exchanged pieces and the game reached a RN vs RN position. Arasan restricted the black king to the h file, it gave a pawn and moved its king forward through the center. Clover couldn't protect its pawns, Arasan captured all of them and was left with two white pawns. The endgame was slow, Arasan gave one pawn away but the 7-man position was still a win. </p><p><i>Standings with 5 rounds to go: Caissa +13, Clover +12, Viridithas +8, DeepSjeng +6, Arasan +5, BlackMarlin +1, Uralochka Velvet -4, Wasp -6, Marvin -7, Tucano -11, Halogen -13. Clover and Caissa are battling for 1st place, Viridithas lost twice and will probably finish 3rd. Arasan still has hope, it won twice against the leaders and reduced the gap to DeepSjeng to 0.5 points. The DeepSjeng-Arasan game 257 may determine the 4th place.</i></p><p><a href="https://tcec-chess.com/#div=l2&game=236&season=25">game 236</a>, <span style="background-color: #04ff00;">Clover</span> - Caissa: There were almost no exchanges after the start, by move 35 only one pair of pawns and one pair of bishops were exchanged. Clover gave a pawn and opened the king side, Caissa surrounded its king with minor pieces for protection. Caissa gave a rook for a bishop and pawn, there was a period of shuffling and then Clover managed to move a rook to the 7th rank. Clover captured a bishop and Caissa's defense collapsed. Clover gained more material and mated.</p><p><i>Standings with 2 rounds to go: Clover +14, Caissa +12, Viridithas +9, DeepSjeng Arasan +6, BlackMarlin +2, Uralochka -3, Velvet -6, Marvin -8, Wasp -9, Tucano -10, Halogen -13. Clover is back in the lead after it beat Caissa. Arasan managed to close the gap to DeepSjeng in 4th after DeepSjeng held a draw against Clover and Viridithas, while Arasan only managed a draw against Caissa playing black with an eval advantage. </i></p><p><a href="https://tcec-chess.com/#div=l2&game=257&season=25">game 257</a>, <span style="background-color: #04ff00;">DeepSjeng</span> - Arasan: Arasan blocked its own knight and lost it for a pawn early in the game. There was no compensation for the lost piece, the engines gradually exchanged pieces until only RN vs R remained. DeepSjeng was patient, it went a pawn up and created a passer, the game ended in a tablebase win.</p><p><i>DeepSjeng secures the 4th promotion spot with this win, it is a point ahead and has a tiebreak advantage over Arasan before the last round.</i></p><p><i><br /></i></p><p><br /></p>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com0tag:blogger.com,1999:blog-4430065842059358622.post-7471937841377257312023-08-12T20:50:00.000+03:002023-08-12T20:50:44.297+03:00Season 25 entrance league statistics<p>A summary <a href="https://drive.google.com/open?id=1dpikbAHWxz1wLcsOzG0kxKCk0Hn67IYJPL8B1wzj_rk" target="_blank">statistics table</a> of previous stages and seasons. </p><p><b>Draw rate, wins</b></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiLOsQIHO5E3_uoOn8b3bDpIiBzwGRU0xA0wGmK9YzAEi8_jpU-jviEOX-o0fPBQGxFn0gQcoYBD2mMpZU2YQXN39F5WwuGW46EfFH7GoWl7MgAAhi-A0QT0cBMPXagTG7LACKwwN5thOiKVuNeQrEEvL9_akH59er8y8iy2SXcbxdQlpRG23BA5ksk2Ig/s480/S25.el.g1.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiLOsQIHO5E3_uoOn8b3bDpIiBzwGRU0xA0wGmK9YzAEi8_jpU-jviEOX-o0fPBQGxFn0gQcoYBD2mMpZU2YQXN39F5WwuGW46EfFH7GoWl7MgAAhi-A0QT0cBMPXagTG7LACKwwN5thOiKVuNeQrEEvL9_akH59er8y8iy2SXcbxdQlpRG23BA5ksk2Ig/s320/S25.el.g1.jpg" width="320" /></a></div><p>Final draw rate was 52.9%. </p><p><b>Game termination</b><br /><br />The three most common game termination causes were:<br />36.5% - SyzygyTB<br />35.8% - TCEC draw rule<br />19.6% - mate<br /><br />There were 3 crashes in the stage, Caissa lost on time twice (once in a winning position), and MrBob crashed once (in a losing position).<br /></p><p><b>Moves per game</b></p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjUsIRcKs2MiczCzxZ1mA7WIFVkAxrKXWXV6QudOq7Qoiq8mrKIUF0f8BSrNzISAp3hqD3s0AW5sSlaaSGKfktOdq-UnZcQOxeZZM748wQL0DNE3jS7FQVq39HtDAYb4vscOOky0p5L2MNnGeeXPoFIsi8ysdKdqGi627JbD-fDxCOoxKaBQUuANgAuA_Y/s480/S25.el.g2.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjUsIRcKs2MiczCzxZ1mA7WIFVkAxrKXWXV6QudOq7Qoiq8mrKIUF0f8BSrNzISAp3hqD3s0AW5sSlaaSGKfktOdq-UnZcQOxeZZM748wQL0DNE3jS7FQVq39HtDAYb4vscOOky0p5L2MNnGeeXPoFIsi8ysdKdqGi627JbD-fDxCOoxKaBQUuANgAuA_Y/s320/S25.el.g2.jpg" width="320" /></a></p><p>Median= 66.5<br />Average= 72.6<br /><br />There were 25 games longer than 100 moves, the longest was 198 moves (MrBob - Caissa, game 86, Caissa won). <br /><br /><b>Time per game (hours)</b></p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgz35fGLK_uNc7nOIo_e75yPf8z6I1gRivXkAk1Lgo1aKG5L5MYCAfgbB5E42yWEc-m3s_nqFOBVnpkEEIWM9WpOT2-z6w_egE1DL7Vu-bCUwHErhVQczyeIkAeHYM3RWwtE46pEqUwjiwDBYzX1Jkwz7xUZ-EWbfPK1GOeblgehmxRwWslgBvIaFDAHbA/s480/S25.el.g3.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgz35fGLK_uNc7nOIo_e75yPf8z6I1gRivXkAk1Lgo1aKG5L5MYCAfgbB5E42yWEc-m3s_nqFOBVnpkEEIWM9WpOT2-z6w_egE1DL7Vu-bCUwHErhVQczyeIkAeHYM3RWwtE46pEqUwjiwDBYzX1Jkwz7xUZ-EWbfPK1GOeblgehmxRwWslgBvIaFDAHbA/s320/S25.el.g3.jpg" width="320" /></a></p><p>Median= 1:01<br />Average= 1:00<br /><br /><b>Openings</b><br /><br />There were variable length book openings in this stage. The first letter of the ECO codes was distributed as follows: </p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgKUJqzv2pCu8SEVsTaMlqcA6io3-Hyd434Ka8ys-5BXmoOkD19wH8o9cnQzDDqTHX3pzgO0Nuuz_eZHSXr1Dppo0prEODzCumc7wu2IVthrfnaERvLgxiHKuncScKzWiwQoQ6d8jVMvreeyR-Cu8dEhSTWYTOD7s2UhaVkFPFdRMQnsNjGzoBFJ14gxZw/s480/S25.el.g4.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgKUJqzv2pCu8SEVsTaMlqcA6io3-Hyd434Ka8ys-5BXmoOkD19wH8o9cnQzDDqTHX3pzgO0Nuuz_eZHSXr1Dppo0prEODzCumc7wu2IVthrfnaERvLgxiHKuncScKzWiwQoQ6d8jVMvreeyR-Cu8dEhSTWYTOD7s2UhaVkFPFdRMQnsNjGzoBFJ14gxZw/s320/S25.el.g4.jpg" width="320" /></a></p><p>The engines had almost no freedom to choose the opening variant, all of the game pairs but one repeated the ECO code and the opening variant twice. In all of the game pairs the first letter of the ECO code was repeated.<br /></p><p><b>Reverse pairs, wins</b></p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhU9vx6HhFsiM5sUbua161teDsQYgrCKkentulRPbkfJpxr3F4JgSSd6F1HpOkS8SPhgo91Mafk-ofvfbJ_BlSZSAxJJ8ygiiaUD2_-CXvaMLPiX7Cxy_MjhdWIqPIl1AjBfXG117pCnq6DziOZ20kxhwEECvg9lOt_IJpyt4vFIiKAVICkYpWpDgZiQ3Q/s480/S25.el.g5.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhU9vx6HhFsiM5sUbua161teDsQYgrCKkentulRPbkfJpxr3F4JgSSd6F1HpOkS8SPhgo91Mafk-ofvfbJ_BlSZSAxJJ8ygiiaUD2_-CXvaMLPiX7Cxy_MjhdWIqPIl1AjBfXG117pCnq6DziOZ20kxhwEECvg9lOt_IJpyt4vFIiKAVICkYpWpDgZiQ3Q/s320/S25.el.g5.jpg" width="320" /></a></p><p><b>Reverse pairs, same moves</b></p><p><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhFfdQKRwxqnvbL_o-RVpAyxShNaO8H_G6tmhYCaT45nlAlGIbq34_CW3-paCcTfN2qdcDrAk0v94iLKcZmaOorn1AlsUs_xgZO8oSg2y0G4ZunrC6zpYjoZ20LT3_zQutiXn9l9SBDJIisMgb2bXUPkRdglkzkABCah9EEinVizXf6P9nYT0n-FFgUQ4k/s480/S25.el.g6.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="480" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhFfdQKRwxqnvbL_o-RVpAyxShNaO8H_G6tmhYCaT45nlAlGIbq34_CW3-paCcTfN2qdcDrAk0v94iLKcZmaOorn1AlsUs_xgZO8oSg2y0G4ZunrC6zpYjoZ20LT3_zQutiXn9l9SBDJIisMgb2bXUPkRdglkzkABCah9EEinVizXf6P9nYT0n-FFgUQ4k/s320/S25.el.g6.jpg" width="320" /></a><b> <br /></b></p><div>Pairs of reverse games diverged quickly, 27.5% diverged immediately out of book, 63.3% of the pairs diverged at most after 1 move. The longest repeated sequence of moves was 11 plys (Clover - Winter, games 51 and 171, Alekhine's defence, four pawns attack, fianchetto variation, Clover won as white) </div><div><br /></div>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com0tag:blogger.com,1999:blog-4430065842059358622.post-27674011674236767552023-08-07T00:53:00.022+03:002023-08-12T11:42:40.562+03:00Season 25 entrance league<p>In season 25 TCEC introduced a new entrance league, but it is just a new name for the qualification league. The Swiss format was abandoned and the entrance league will be a double RR. The 16 engines playing were chosen using the results of the Swiss event that was played earlier.</p><p>The engines that will play in the entrance league are:</p><p>relegated from season 24 league 2 - Booot, Expositor<br />played in Swiss season 24 - Smallbrain, Mantissa, MrBob, StockDory, Stash, Weiss, Winter, Equisetum, ChessFighter<br />new to TCEC - Clover, Caissa, DeepSjeng, Viridithas, BlackCore</p><p><b>Final standings</b></p><p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjSfGS4Z3Is30NbVPXGcO29BTYDhH4_LC1MGzUWeVjMLk4Aytrg8pTxWDg5QZGH_pIDwWkoKH00Y8TiEBE1n6Bk8AwnQ7oEHG44fRKp86U6Xe1LWk52FcpR0DYlxjpukWiCZL6id3yvHbuF8HMRYb8faOqwfz0GTQO-UGjIP0lR65-ceoGT5snvfTCczk0/s640/tab1.png" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="640" data-original-width="634" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjSfGS4Z3Is30NbVPXGcO29BTYDhH4_LC1MGzUWeVjMLk4Aytrg8pTxWDg5QZGH_pIDwWkoKH00Y8TiEBE1n6Bk8AwnQ7oEHG44fRKp86U6Xe1LWk52FcpR0DYlxjpukWiCZL6id3yvHbuF8HMRYb8faOqwfz0GTQO-UGjIP0lR65-ceoGT5snvfTCczk0/s320/tab1.png" width="317" /></a></div><br /><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi_BCWnky-1KIPcKaOqBcPfWKmV3KCehUKA1XyWAxNRBdEzRM18O5ywPuOvrVktlgdopkIR8No2_qaHB30oU6NWSCgKsB05ilNJXAOVlthAdnLf8BvlbWAtsWpcOJpovIhu2M2AprmfCzdbDVdyKnzwrHS5XyzUHHpLWsnY6MmSWFheJ0VVdyzNjy3AUC0/s634/tab2.png" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="633" data-original-width="634" height="319" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi_BCWnky-1KIPcKaOqBcPfWKmV3KCehUKA1XyWAxNRBdEzRM18O5ywPuOvrVktlgdopkIR8No2_qaHB30oU6NWSCgKsB05ilNJXAOVlthAdnLf8BvlbWAtsWpcOJpovIhu2M2AprmfCzdbDVdyKnzwrHS5XyzUHHpLWsnY6MmSWFheJ0VVdyzNjy3AUC0/s320/tab2.png" width="320" /></a></div><br /><b><br /></b><p></p><p>Viridithas, Clover, DeepSjeng and Caissa advance to league 2. They led the league from the start together with Booot and SmallBrain. Caissa lost twice on time and in the final rounds Booot and SmallBrain came close to it, however a win in the last round secured 4th place for Caissa.</p><p>All 4 promoting engines are new to the TCEC leagues. They played in the Swiss event that started the season, their results in the league were better than in the Swiss event which also includes a luck factor.</p><p>The 4 advancing engines will play in league 2 together with:<br />played in season 25 league 1 - BlackMarlin Marvin <br />played in season 25 league 2 - Uralochka Arasan Wasp Halogen Velvet Tucano</p><p><b>Interesting games</b></p><p><a href="https://tcec-chess.com/#div=el&game=1&season=25">game 1</a>, <span style="background-color: #04ff00;">Caissa</span> - Booot : Caissa used the weak black pawn structure on the <span>queen side, first it went a pawn up and then it captured a second pawn and created two passers. Caissa gave a rook for a bishop to connect the passers, Booot started to lose material but could only capture one passer, Caissa forced mate. </span></p><p><a href="https://tcec-chess.com/#div=el&game=2&season=25">game 2</a>, <span style="background-color: #04ff00;">Winter</span> - Mantissa: Winter went a pawn up, then gradually reduced to a RBN vs RBN position. Mantissa gave another pawn to free its bishop, after exchanging bishops Winter pushed pawns to win.</p><p><a href="https://tcec-chess.com/#div=el&game=11&season=25">game 11</a>, MrBob - Viridithas: The game reached a RRB vs RRB position, the black king was trapped in the corner and it seemed MrBob had the advantage. However, MrBob blundered and allowed Viridithas to exchange the remaining queen side pawns. MrBob was a pawn up but the endgame was a draw.</p><p><a href="https://tcec-chess.com/#div=el&game=21&season=25">game 21</a>, <span style="background-color: #04ff00;">Clover</span> - Weiss: After an early series of exchanges lover was up a pawn with connected passers on the queen side. Clover pushed the passers slowly, Weiss managed to separate them but both reached the 7th rank eventually. Weiss lost a bishop for one passer, Clover queened the other and mated.</p><p><a href="https://tcec-chess.com/#div=el&game=27&season=25">game 27</a>, <span style="background-color: #04ff00;">DeepSjeng</span> - Equisetum: After 35 moves the engines opened the center and DeepSjeng went a pawn up. DeepSjeng used threats on the black king to gain an exchange and reduce to a RR vs RN position. The game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=el&game=32&season=25">game 32</a>, <span style="background-color: #04ff00;">Winter</span> - Stash: The center was blocked, evals gradually increased while Winter doubled rooks on the open c file. Winter moved a rook forward and traded it for two minors, then opened the king side and attacked the black king. Stash lost material and was mated.</p><p><a href="https://tcec-chess.com/#div=el&game=33&season=25">game 33</a>, Stash - <span style="background-color: #04ff00;">Booot</span>: The game reached a RRB vs RBN position with black two pawns up. Booot slowly pushed connected passers forward, Stash pushed a passer to the 7th rank where it was blocked. It took Booot 25 moves to captured the white passer and queen a pawn safely, the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=el&game=36&season=25">game 36</a>, <span style="background-color: #04ff00;">Clover</span> - Mantissa: After the engines opened the position with exchanges the game reached a QRN vs QRB position, pawns were equal but Clover had a passer. Mantissa managed to stop the passer but Clover reduced to a won king and pawns ending.</p><p><a href="https://tcec-chess.com/#div=el&game=47&season=25">game 47</a>, <span style="background-color: #04ff00;">Winter</span> - BlackCore: BlackCore captured a pawn but its king was exposed. Winter created a passer and BlackCore lost a bishop to stop it. In a QRN vs QR position Winter attacked the black king, captured the queen and mated.</p><p><a href="https://tcec-chess.com/#div=el&game=51&season=25">game 51</a>, <span style="background-color: #04ff00;">Clover</span> - Winter: Winter traded a knight for a rook, but Clover had a passer on the wueen side and the black queen was far on the king side. After exchanging queens Clover gained the material back and the white king moved to support the passer. Winter lost a bishop for the passer, in a bishop vs pawns ending Clover used zugzwang to win.</p><p><a href="https://tcec-chess.com/#div=el&game=52&season=25">game 52</a>, <span style="background-color: #04ff00;">Viridithas</span> - Caissa: The game reached a RB vs RB position and was heading for a draw when Caissa blundered and exchange rooks. The bishops were of opposite colors and Viridithas was only one pawn up, but the black king was trapped and the white king was free to support a passer. Caissa couldn't stop a queening, game over.</p><p><a href="https://tcec-chess.com/#div=el&game=53&season=25">game 53</a>, <span style="background-color: #04ff00;">Equisetum</span> - Mantissa: Most pieces were on the queen side, Equisetum shifted to attack the black king on the other side. Mantissa gave a pawn and hid its king behind a white passer, Equisetum captured a second pawn and reduced to a QR vs QR position. Mantissa lost more material and was mated.</p><p><a href="https://tcec-chess.com/#div=el&game=57&season=25">game 57</a>, <span style="background-color: #04ff00;">Booot</span> - DeepSjeng: The game reached a RN vs RB position with white a pawn up. DeepSjeng could have held perhaps, but it didn't play accurately enough. Booot gave back the pawn, opened the king side and moved its king forward. Eventually it captured a pawn and reduced to a 7-man win.</p><p><a href="https://tcec-chess.com/#div=el&game=61&season=25">game 61</a>, <span style="background-color: #04ff00;">Caissa</span> - Equisetum: Equisetum gave a rook for a knight and pawn, Caissa patiently exchanged pieces until only QRN vs QBB remained. Caissa had a passer, after queens were exchanged Equisetum was forced to lose a bishop to stop the passer. The game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=el&game=68&season=25">game 68</a>, <span style="background-color: #04ff00;">Equisetum</span> - Winter: Both kings were exposed and under attack, Equisetum had more pieces involved and was more dangerous. After most pieces were exchanged the game reached a Q vs RN position, Equisetum chased the black king away and queened a passer to win. </p><p><a href="https://tcec-chess.com/#div=el&game=72&season=25">game 72</a>, <span style="background-color: #04ff00;">DeepSjeng</span> - Weiss: Weiss gave a knight for two pawns to try to free some space for its pieces. DeepSjeng mostly shuffled for a while, Weiss tried to protect its king and eventually lost a few pawns. DeepSjeng gained more material and queened a passer to win.</p><p><a href="https://tcec-chess.com/#div=el&game=81&season=25">game 81</a>, <span style="background-color: #04ff00;">Clover</span> - Booot: Evals gradually increased as the engines exchanged pawns and pieces though material was equal. Booot had two isolated pawns to protect and its pieces were passive. Eventually Clover created a passer and Booot gave a rook for a bishop. Booot couldn't stop the passer without losing more material, game over.</p><p><a href="https://tcec-chess.com/#div=el&game=87&season=25">game 87</a>, <span style="background-color: #04ff00;">DeepSjeng</span> - Mantissa: Mantissa was up a pawn but the king side was open and the black king was in danger. The engines shuffled for a long time, when the black king tried to run to the center DeepSjeng moved its pieces forward to attack. Mantissa lost material and was mated.</p><p><a href="https://tcec-chess.com/#div=el&game=91&season=25">game 91</a>, <span style="background-color: #ffa400;">Caissa</span> - DeepSjeng: In a drawn opposite color bishops ending Caissa failed to move and lost on time.</p><p><a href="https://tcec-chess.com/#div=el&game=97&season=25">game 97</a>, <span style="background-color: #04ff00;">Viridithas</span> - Booot: When the position opened the black king was more exposed and vulnerable. Viridithas used this to capture a pawn and to create connected passers. In a RRB vs RRB position Booot could stop the passers, Viridithas queened to win. </p><p><a href="https://tcec-chess.com/#div=el&game=102&season=25">game 102</a>, <span style="background-color: #04ff00;">DeepSjeng</span> - Winter: DeepSjeng captured a rook for a knight and pawn early in the game, then a series of exchanges reduced to a RN vs R position with black two pawns up. Winter traded pawns but DeepSjeng held on to one last pawn to ensure the win.</p><p><a href="https://tcec-chess.com/#div=el&game=105&season=25">game 105</a>, <span style="background-color: #04ff00;">Booot</span> - Mantissa: Mantissa moved its king without castling, blocking its king side rook. Booot sacrificed a knight for two pawns and exposed the black king, Mantissa gave back the piece and the game reached a rook ending with white a pawn up. Booot captured another pawn and queened a passer to win.</p><p><a href="https://tcec-chess.com/#div=el&game=111&season=25">game 111</a>, <span style="background-color: #04ff00;">Clover</span> - SmallBrain: The engines gradually exchanged pieces and pawns while evals increased. The game reached a RB vs RN position, SmallBrain could not defend its pawns and Clover captured them all. The two white pawns left were enough to win.</p><p><a href="https://tcec-chess.com/#div=el&game=112&season=25">game 112</a>, <span style="background-color: #04ff00;">Viridithas</span> - Equisetum: Evals were stable until move 40 though white was a pawn up. Equisetum gave a rook for a knight, the game reached a QR vs QN position and Viridithas went a pawn up. Equisetum lost its queen for a passer, game over.</p><p><i>Standings after RR1: Viridithas +7, Clover DeepSjeng +6, Booot Caissa +4, SmallBrain +3, Winter +1, Mantissa Weiss 0, Equisetum -1, BlackCore -2, Expositor -4, Stash MrBob -5, StockDory -6, ChessFighter -8. The newcomers are leading at the half, there are 4 of them in the top 6 engines that are fighting for 4 qualification spots. Winter also started well but then fell back from the leaders.</i></p><p><a href="https://tcec-chess.com/#div=el&game=129&season=25">game 129</a>, <span style="background-color: #04ff00;">SmallBrain</span> - Booot: Evals were stable and the engines mostly shuffled, then on move 44 Booot gave a rook for a bishop. After a few exchanges and more shuffling SmallBrain gave a rook for two knights and opened the position. In a QRN vs QR position Booot was 3 pawns up, SmallBrain captured pawns and reduced to a winning king and pawns ending.</p><p><a href="https://tcec-chess.com/#div=el&game=137&season=25">game 137</a>, <span style="background-color: #04ff00;">Booot</span> - Winter: Booot was a pawn up from the start, the engines exchanged pieces and pawns and the game reached a rook ending. Winter could have held perhaps, but in the end the game reached a tablebase win.</p><p><a href="https://tcec-chess.com/#div=el&game=148&season=25">game 148</a>, <span style="background-color: #04ff00;">Viridithas</span> - Weiss: Weiss castled long and Viridithas slowly increased the pressure on the queen side. Viridithas pushed pawns and opened the queen side, then used an attack on the black king to capture pawns. The engines reduced to a rook ending with white 3 pawns up, enough for a win.</p><p><a href="https://tcec-chess.com/#div=el&game=152&season=25">game 152</a>, <span style="background-color: #04ff00;">Stash</span> - Winter: Stash was a pawn up but evals were stable and the engines shuffled. After move 60 Winter played inaccurately, it let Stash open files and its king was in danger. By the time Winter realized it was in trouble Stash captured a rook for a bishop. The game reached a R vs N ending, Stash queened a passer to win.</p><p><a href="https://tcec-chess.com/#div=el&game=165&season=25">game 165</a>, <span style="background-color: #04ff00;">Viridithas</span> - Mantissa: Viridithas gave pawns to open files and attack the uncastled black king. Mantissa was 4 pawns up when Viridithas captured a rook, in a QRB vs QRB position Viridithas chased the black king. Mantissa lost material and the game ended in a tablebase win.</p><p><a href="https://tcec-chess.com/#div=el&game=167&season=25">game 167</a>, <span style="background-color: #04ff00;">BlackCore</span> - Winter: BlackCore prepared an attack on the king side, most black pieces waited with only a little room to move. BlackCore opened the king side and a series of exchanges reduced to a QN vs RRN position. Winter gave the knight for a passer, all the pawns were captured and the game ended in a tablebase win.</p><p><i>Standings with 8 rounds to go: Viridithas +10, DeepSjeng +8, Clover +7, Booot Caissa +6, SmallBrain +5, Equisetum +2, Weiss +1, Winter Mantissa -1, BlackCore -4, Stash -5, Expositor -6, MrBob StockDory -9, ChessFighter -10. The top 6 engines are still in the race for qualification. Booot lost to SmallBrain but it used wins against weaker engines to stay in joint 4th place. Equisetum won 3 games and climbed in the table, though it will probably not close the gap to the leaders.</i></p><p><a href="https://tcec-chess.com/#div=el&game=180&season=25">game 180</a>, <span style="background-color: #04ff00;">SmallBrain</span> - Mantissa: After shuffling for a while the engines exchanged pieces and reduced to a RN vs RN position. SmallBrain had a passer on the king side, it captured a pawn and created a second passer on the queen side. SmallBrain exchanged rooks, queened a passer and mated.</p><p><a href="https://tcec-chess.com/#div=el&game=188&season=25">game 188</a>, Winter - Equisetum: Winter was up a rook for a bishop and seemed to have an advantage. Then it let Equisetum reduce to a RN vs BN position with the white rook trapped. Evals dropped to 0 and the game was adjudicated a draw. </p><p><a href="https://tcec-chess.com/#div=el&game=189&season=25">game 189</a>, <span style="background-color: #04ff00;">Caissa</span> - SmallBrain: Caissa opened the king side and threatened the black king. SmallBrain was a pawn up but its pieces were on the queen side and struggled to help. Caissa forked the black queen and rook with its knight, SmallBrain escaped but lost two pawns. The pressure on the black king increased, Caissa gained material and the game ended in a tablebase win. </p><p><a href="https://tcec-chess.com/#div=el&game=193&season=25">game 193</a>, <span style="background-color: #04ff00;">Weiss</span> - Booot: Evals increased gradually from the start, material was equal but Weiss had a space advantage. The engines opened files and reduced to a RRN vs RRN position, Weiss created a passer and went a pawn up. After exchanging a pair of rooks Weiss captured two more pawns, Booot gave a knight for one passer and the rook for another, game over.</p><p><i>Standings with 3 rounds to go: Viridithas +12, DeepSjeng Clover +9, Caissa +8, Booot SmallBrain +6, Equisetum Weiss +3, Winter -1, Mantissa -2, BlackCore -5, Stash -6, Expositor -7, MrBob ChessFighter -11, StockDory -13. The 4 qualification spots are almost decided. Caissa beat SmallBrain and it is holding on to 4th place. Booot also moved a step further away from qualification after its loss to Weiss. </i></p><p><a href="https://tcec-chess.com/#div=el&game=218&season=25">game 218</a>, <span style="background-color: #04ff00;">Clover</span> - Equisetum: Clover gave a pawn and a bishop to attack the black king. Equisetum gave the material back and the game reached a RN vs RB position. The white rook was on the 7th rank, Clover moved its king forward and captured pawns. Equisetum lost its pieces for passers, game over.</p><p><a href="https://tcec-chess.com/#div=el&game=223&season=25">game 223</a>, <span style="background-color: #ffa400;">Caissa</span> - Weiss: Evals increased with most pieces and pawns still on the board. Caissa gave a rook for a bishop to create an advanced passer, then captured a pawn and connected a second passer. However, after some shuffling without a clear plan Caissa failed to move and lost on time. This is its second crash in the league.</p><p><i>Booot and SmallBrain drew their games in round 28, with 2 rounds to go they are now only 0.5 points behind Caissa in 4th place.</i></p><p><i>Caissa, Booot and SmallBrain all drew their games in round 29, the 4th place will be decided in the last round. Caissa has a head to head tiebreak advantage against both Booot and SmallBrain.</i></p><p><a href="https://tcec-chess.com/#div=el&game=233&season=25">game 233</a>, <span style="background-color: #04ff00;">Booot</span> - Equisetum: Evals increased while the engines exchanged pieces, the game reached a RRN vs RRB position with the black bishop stuck behind pawns. Booot captured a pawn and reduced to a king and pawns ending. The one pawn advantage was enough to win.</p><p><i>Booot still has a chance to finish in 4th place, it needs Caissa to lose (or crash). SmallBrain drew its game and it is out of the race.</i></p><p><a href="https://tcec-chess.com/#div=el&game=240&season=25">game 240</a>, <span style="background-color: #04ff00;">Caissa</span> - Mantissa: Caissa placed a protected knight on e6, Mantissa moved its king without castling. Caissa opened the h file and the black king was in danger, Mantissa exchanged pieces and the game reached a RN vs BN position with white a pawn up. Caissa had connected passers, it gave the rook for a knight and used 7-man tablebases to win.</p><p><i>With this win Caissa finishes 4th ahead of Booot.</i></p><p><i><br /></i></p>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com0tag:blogger.com,1999:blog-4430065842059358622.post-83996138145409172342023-07-01T19:27:00.039+03:002023-11-03T16:50:53.915+02:00Season 25 qualification/Swiss<p>The TCEC season 25 has started with a Swiss event. As in season 24 the results of the Swiss event will help determine which engines play in the TCEC leagues that follow, so it is in part a qualification stage. I'm not exactly sure about the competition format, according to the currently published TCEC rules there will be a new entrance league before league 2, consisting of 16 engines where 6 are decided by the Swiss event. It is not clear which engines are in the race for the entrance league and which are already assured a place in the leagues. This is because there was no equivalent of an entrance league in season 24, and also because several engines that played in the leagues last season will not play this season. It is not clear whether the organizers will decide to increase the number of promotions per league, or to push engines up and fill the vacant spots while keeping the promotions as before. </p><p>There were 13+8+6=27 engines that played in the leagues in season 24. The following engines will not play this season:<br />Berserk, Koivisto - season 24 premier league<br />Nemorino - season 24 league 2, relegated<br />Zahak, Counter, Amoeba, Cheese - season 24 qualification / Swiss</p><p>Two had a reserved spot in the leagues. This leaves 24 engines including 3 that relegated from league 2, perhaps those will get an automatic spot in the entrance league. Even counting these, it appears there are 21 engines fighting for 16 spots of the entrance league, not a strong filter. </p><p>Potential contestants are:<br />relegated from season 24 league 2 - Tucano, Booot (crash bug fixed), Expositor<br />played in Swiss season 24 - Smallbrain, Mantissa, MrBob, StockDory (was StockNemo), Stash, Weiss, Winter, Equisetum (was Drofa), ChessFighter, Bagatur, ice4, 4ku<br />new to TCEC - OliThink, Clover, Caissa, DeepSjeng, Viridithas, BlackCore</p><p><b>Final standings</b></p><p>Viridithas MrBob +2, Caissa SmallBrain Weiss Clover Equisetum +1, DeepSjeng BlackCore Expositor Stash Tucano 0, Booot Winter Mantissa ChessFighter -1, StockDory -2, ice4 -8, 4ku -11, Bagatur -14, OliThink -16. </p><p>Viridithas led the event after the first 3 rounds with two double wins, one against Weiss. As a result it had to face stronger engines, in the next 8 rounds it played and lost against Stockfish, Leela, KomodoDragon and Igel, the 4 engines that led the event in the end. Still it was able to finish first in the qualification section. On the other hand, MrBob used a lot of Swiss luck to finish with the same score as Viridithas. MrBob had 3 double wins against 4ku, Bagatur and OliThink, and it didn't have to face a single engine that is really strong (in this field).</p><p>The newcomer engines did well in this event, 5 of them finished within one point of the lead. Only OliThink turned out to be weak and finished last.</p><p>In the first rounds I was somewhat surprised by the weakness of Stoofvlees and ScorpioNN, both engines that I thought were strong. Stoofvlees lost against Seer and then only drew its next 3 game pairs. It managed to recover after this, winning a few game pairs and losing only once more in the final round against Stockfish. Stoofvlees finished with a +2 score. ScorpioNN only drew against Equisetum and lost to Arasan in the first rounds, it had a few wins as well but stayed in the middle of the table. ScorpioNN finished with a +1 score.</p><p>The engines that will play in the season 25 leagues was published on the TCEC wiki. The organizers chose to push the engines up to fill the empty spots left by engines that dropped out. As a result there were fewer relegations than those published in the previous seasons. The engines that will play in the entrance league are the top 16 engines in the final standings, from Viridithas to StockDory, not counting Tucano which will play in league 2. </p><p><b>Interesting games</b></p><p><a href="https://tcec-chess.com/#div=sw5&game=14&season=25">game 14</a>, ChessFighter - DeepSjeng: ChessFighter was up a pawn in a QB vs QB position. It decided to give the bishop for pawns and this allowed DeepSjeng to force a perpetual check draw. A missed chance for ChessFighter.</p><p><a href="https://tcec-chess.com/#div=sw5&game=26&season=25">game 26</a>, Winter - Clover: Winter was sure it was winning when it reduced to a N vs R ending with 3 pawns up. However, Clover pushed its last pawn to the 2nd rank and this was enough to hold a draw even if Winter queened a pawn.</p><p><a href="https://tcec-chess.com/#div=sw5&game=45&season=25">game 45</a>, 4ku - ice4: 4ku reduced to a RB vs BNN position with two pawns up. It pushed a passer to the 7th rank and seemed to be close to winning, but then it chose to reach a drawn opposite color bishops ending. </p><p><a href="https://tcec-chess.com/#div=sw5&game=63&season=25">game 63</a>, <span style="background-color: #04ff00;">Equisetum</span> - ScorpioNN: Equisetum was up a knight for a pawn early, ScorpioNN captured another pawn but Equsetum kept its piece advantage and won in a QRB vs QR position. ScorpioNN won the reverse game, perhaps the opening was too unbalanced. </p><p><a href="https://tcec-chess.com/#div=sw5&game=82&season=25">game 82</a>, <span style="background-color: #04ff00;">Viridithas</span> - BlackMarlin: Viridithas slowly increased the pressure until it captured a pawn and created a passer. In a RB vs RN position Viridithas captured more pawns and reduced to a tablebase win. BlackMarlin only drew the reverse. </p><p><a href="https://tcec-chess.com/#div=sw5&game=84&season=25">game 84</a>, Stash - Weiss: Stash reached a winning RB vs R position, but it blundered after rooks were exchanged. Weiss managed to exchange pawns and Stash was left with one pawn and the wrong bishop, draw.</p><p><a href="https://tcec-chess.com/#div=sw5&game=88&season=25">game 88</a>, <span style="background-color: #04ff00;">Winter</span> - ChessFighter: The game reached a QR vs RBN position, each side with two passers. The black pawns were more advanced and for a while Winter was not sure it could win. ChessFighter could have held a draw perhaps, in the end it allowed a piece exchange that reduced to a tablebase win. ChessFighter won the reverse, the game pair was a draw.</p><p><a href="https://tcec-chess.com/#div=sw5&game=96&season=25">game 96</a>, <span style="background-color: #04ff00;">Expositor</span><span style="background-color: white;"> </span>- Stoofvlees: Expositor increased its opening advantage, the engines reduced to a RB vs RB position quickly and Expositor was a pawn up. Expositor captured a second pawn and used a passer to gain material and win. Stoofvlees won the reverse, still an unexpected loss to a weaker opponent.</p><p><a href="https://tcec-chess.com/#div=sw5&game=126&season=25">game 126</a>, Weiss - <span style="background-color: #04ff00;">Viridithas</span>: Viridithas equalized in a closed position, then took control of the game in a QRN vs QRB position with a passer on the 2nd rank. It took a while to open the position, Viridithas captured the knight for the passer and won in a Q vs QB ending. Viridithas also won the reverse. </p><p><i>Standings after 3 double rounds: </i><i>Viridithas +5, Weiss DeepSjeng Caissa +1, Stash BlackCore Booot</i><i> 0, </i><i>Equisetum Mantissa </i><i>Expositor</i><i> Smallbrain</i><i> </i><i>Clover </i><i>ice4</i><i> </i><i>Tucano -1, StockDory Winter ChessFighter MrBob Bagatur -2,</i><i> 4ku -3,</i><i> OliThink -4. Viridithas is actually leading the event, not only the entrance league candidates. It had two double wins in 3 double rounds, but now will face stronger opponents. Caissa and DeepSjeng also started well.</i></p><p><a href="https://tcec-chess.com/#div=sw5&game=131&season=25">game 131</a>, Bagatur - <span style="background-color: #04ff00;">ChessFighter</span>: All the white pieces were on the queen side in a closed position, ChessFighter opened the king side and attacked the white king to win. ChessFighter also won as white.</p><p><a href="https://tcec-chess.com/#div=sw5&game=138&season=25">game 138</a>, <span style="background-color: #04ff00;">Equisetum</span> - Stoofvlees: Stoofvlees had a bishop pair, but Equisetum had strong knights and advanced passers. Equisetum used its passers to gain material and win. Stoofvlees won the reverse, it still has difficulties against weaker opponents. </p><p><a href="https://tcec-chess.com/#div=sw5&game=156&season=25">game 156</a>, <span style="background-color: #04ff00;">Caissa</span><span style="background-color: white;"> </span>- Seer: When the position opened Caissa was down a pawn but had an advanced passer. Caissa traded the passer for a knight, then reduced to a winning RBN vs RN position. Seer won the reverse game, Caissa drew the game pair.</p><p><a href="https://tcec-chess.com/#div=sw5&game=168&season=25">game 168</a>, Viridithas - Igel: Viridithas had an advantage in a QB vs QB position but gave it up when it exchanged all pieces. It managed to capture 3 pawns, but with 3 sets of doubled pawns it could only get a draw. </p><p><a href="https://tcec-chess.com/#div=sw5&game=177&season=25">game 177</a>, <span style="background-color: #04ff00;">BlackCore</span> - Halogen: BlackCore was up a pawn in a B vs N position, and it managed to win in a long endgame. Halogen won the reverse game.</p><p><a href="https://tcec-chess.com/#div=sw5&game=179&season=25">game 179</a>, Mantissa - <span style="background-color: #04ff00;">Stoofvlees</span>: Stoofvlees equalized with most pawns on the board, then reduced to a QB vs QB position with connected passers. After some shuffling the queens were exchanged and Stoofvlees captured two pawns. Mantissa couldn't hold the opposite color bishops ending, Stoofvlees pushed its passers to win. Stoofvlees also won the reverse game. </p><p><a href="https://tcec-chess.com/#div=sw5&game=200&season=25">game 200</a>, <span style="background-color: #04ff00;">Caissa</span> - DeepSjeng: Caissa captured a knight for two pawns after the start. It then traded its queen for two rooks, and reached a RRN vs Q imbalance with equal pawns. It used passers to gain a piece and then mated. DeepSjeng started the reverse game similarly but couldn't convert the initial advantage to a win.</p><p><i>Standings after 5 double rounds: Viridithas +3, Caissa +2, SmallBrain +1, DeepSjeng Expositor Clover 0, Weiss ChessFighter Stash BlackCore Booot Tucano StockDory -1, Equisetum MrBob Winter -2, Mantissa 4ku -3, ice4 Bagatur -4, OliThink -6. Viridithas still leads, though it lost twice against strong opponents. Caissa is in second place after beating DeepSjeng, SmallBrain climbs to 3rd.</i></p><p><a href="https://tcec-chess.com/#div=sw5&game=215&season=25">game 215</a>, 4ku - <span style="background-color: #04ff00;">MrBob</span>: 4ku traded its queen for RN and 3 pawns early in the game. There was a long shuffle in a RNN vs QR position, a few moves before a 50-move draw 4ku blundered. MrBob managed to capture pawns, then it used a passer on the 2nd rank to reduce to a tablebase win. MrBob also won the reverse game.</p><p><a href="https://tcec-chess.com/#div=sw5&game=224&season=25">game 224</a>, <span style="background-color: #04ff00;">Booot</span> - Weiss: The game reached a RNN vs RR position with most pawns on the board. Booot used the knights to block the black rooks, the white king moved forward and Booot captured pawns. It used its passers to win. </p><p><a href="https://tcec-chess.com/#div=sw5&game=230&season=25">game 230</a>, <span style="background-color: #04ff00;">Clover</span> - Wasp: Clover was up a pawn early, the game reached a QNN vs QBB position. Clover pushed a passer and Wasp gave a bishop for it. The material advantage was enough for a win.</p><p><a href="https://tcec-chess.com/#div=sw5&game=238&season=25">game 238</a>, <span style="background-color: #04ff00;">SmallBrain</span> - SlowChess: SmallBrain was a pawn up early, after a long period of mostly shuffling the position opened and SmallBrain created a passer. Eventually SlowChess gave a bishop for the passer and the game reached a winning 7-man RN vs R position. SlowChess won the reverse game.</p><p><a href="https://tcec-chess.com/#div=sw5&game=244&season=25">game 244</a>, <span style="background-color: #04ff00;">Caissa</span> - Minic: Minic didn't castle and one of its rooks was trapped. Caissa sacrificed a knight and exposed the black king, Minic lost its queen for a rook. Caissa chased the black king in a QR vs RRB position, it gained material to win. Minic won the reverse game.</p><p><a href="https://tcec-chess.com/#div=sw5&game=250&season=25">game 250</a>, <span style="background-color: #04ff00;">Leela</span> - Viridithas: Evals were stable for a long time with almost no exchanges, after the queen side opened Leela reduced to a same color bishops ending. It created 3 passers and gave its bishop, Viridithas couldn't stop all the passers and was too late with its own ones. </p><p><a href="https://tcec-chess.com/#div=sw5&game=260&season=25">game 260</a>, <span style="background-color: #04ff00;">Weiss</span> - Equisetum: The black king stayed in the center, Weiss doubled rooks on the half open e file and increased the pressure. Eventually Weiss gained material and broke through the center to force mate.</p><p><a href="https://tcec-chess.com/#div=sw5&game=261&season=25">game 261</a>, <span style="background-color: #04ff00;">Winter</span> - Stash: Winter slowly increased the pressure on the king side, after opening the f file Winter captured a pawn and reduced to a double knight ending. Two advanced passers gave Winter the win. </p><p><a href="https://tcec-chess.com/#div=sw5&game=277&season=25">game 277</a>, <span style="background-color: #04ff00;">DeepSjeng</span> - Arasan: DeepSjeng captured a rook for a bishop early in the game. Evals increased slowly, after a long period with no exchanges the engines reduced to a RB vs R ending which DeepSjeng converted. In the reverse game Arasan did not capture the rook, but it still won. </p><p><a href="https://tcec-chess.com/#div=sw5&game=279&season=25">game 279</a>, <span style="background-color: #04ff00;">SmallBrain</span> - ScorpioNN: The game reached a QRR vs QRR position with white a pawn up. The black queen was almost trapped by the time ScorpioNN moved it to a more useful location SmallBrain captured a second pawn, then it reduced to a won queen ending. ScorpioNN won the reverse game.</p><p><a href="https://tcec-chess.com/#div=sw5&game=281&season=25">game 281</a>, <span style="background-color: #04ff00;">Clover</span> - rofChade: Clover captured a knight for two pawns, the engines slowly exchanged pieces until only QBN vs QB remained. rofChade had connected passers and Clover played slowly and carefully. Clover managed to capture pawns and control the passers, after exchanging queens it had enough material to win. rofChade won the reverse game. </p><p><i>Standings after 7 double rounds: Caissa Viridithas SmallBrain DeepSjeng Clover BlackCore +1, Booot MrBob Expositor Mantissa StockDory ChessFighter Weiss Winter -1, ice4 Tucano -2, Stash Equisetum -3, 4ku -6, Bagatur -7 OliThink -8. A group of 6 engines are leading, those that were ahead met strong opponents and lost their lead. There will be more head to head games within this group now. A second group of 8 engines is 1 point behind, these can jump higher is they chance to meet one of the engines at the bottom.</i></p><p><a href="https://tcec-chess.com/#div=sw5&game=305&season=25">game 305</a>, <span style="background-color: #04ff00;">ChessFighter</span> - Wasp: ChessFighter was up a rook for a bishop and two pawns. Wasp thought its passers were strong enough to secure a draw but it was forced to lose material when ChessFighter attacked the black king. The game reached a RN vs N position, Wasp was up 3 pawns but the white rook captured them to win. Wasp won the reverse game.</p><p><a href="https://tcec-chess.com/#div=sw5&game=308&season=25">game 308</a>, <span style="background-color: #04ff00;">Weiss</span> - Winter: Winter was weak on the dark squares, Weiss used this to attack the black king. Weiss sacrificed two pieces but Winter had to give the material back to avoid mate. The Q vs RN ending with three white pawns was a win for Weiss. The reverse game was a draw. </p><p><a href="https://tcec-chess.com/#div=sw5&game=310&season=25">game 310</a>, <span style="background-color: #04ff00;">Booot</span> - Expositor: Booot was up a pawn from the opening, the engines reduced to a knight ending. After exchanging most pawns Booot had an advanced passer that Expositor couldn't stop, game over. The reverse game was a draw. </p><p><a href="https://tcec-chess.com/#div=sw5&game=317&season=25">game 317</a>, <span style="background-color: #04ff00;">Viridithas</span> - DeepSjeng: Viridithas trapped the black LS bishop, after exchanging queens Viridithas captured a pawn. Then it moved a rook forward and captured a second pawn. It used a passer to captured the trapped bishop, the game ended in a tablebase win. The reverse game was a draw.</p><p><a href="https://tcec-chess.com/#div=sw5&game=319&season=25">game 319</a>, <span style="background-color: #04ff00;">Caissa</span> - SmallBrain: SmallBrain gave a rook for a knight to open the queen side and attack the white king. Caissa kept its king safe and reduced to a RN vs BN position, then slowly captured all the remaining black pawns to win. The reverse game was a draw.</p><p><a href="https://tcec-chess.com/#div=sw5&game=345&season=25">game 345</a>, <span style="background-color: #04ff00;">Expositor</span> - ChessFighter: The game reached a RB vs RB position with white a pawn up. Expositor exchanged the pieces and won the king and pawns endgame. The reverse game was a draw.</p><p><a href="https://tcec-chess.com/#div=sw5&game=348&season=25">game 348</a>, <span style="background-color: #04ff00;">Marvin</span> - Mantissa: Mantissa was not careful enough with its king's safety. Marvin opened the king side, Mantissa started to lose material and was mated quickly. The reverse game was a draw.</p><p><a href="https://tcec-chess.com/#div=sw5&game=350&season=25">game 350</a>, <span style="background-color: #04ff00;">Stash</span> - Wasp: Evals were stable for a long while in a closed position. After the position opened and only RRN vs RRB were left Stash created a passer and used it to reduce to a won knight vs pawns ending. Wasp won the reverse game.</p><p><a href="https://tcec-chess.com/#div=sw5&game=355&season=25">game 355</a>, <span style="background-color: #04ff00;">SmallBrain</span> - Weiss: The game reached a RRB vs RRB position and SmallBrain captured a pawn. After a shuffle period SmallBrain exchanged a pair of rooks and captured a second pawn, then queened a passer to win. The reverse game was a draw.</p><p><a href="https://tcec-chess.com/#div=sw5&game=363&season=25">game 363</a>, <span style="background-color: #04ff00;">SlowChess</span> - Clover: Clover played a few weak moves, then traded both bishops for knights. The black king was in danger and Clover exchanged pieces until only RRB vs RNN remained. SlowChess created a passer and queened to win. The reverse game was a draw.</p><p><a href="https://tcec-chess.com/#div=sw5&game=366&season=25">game 366</a>, <span style="background-color: #04ff00;">Viridithas</span> - Revenge: Viridithas opened the king side and Revenge had to protect its king. For a long while the engines shuffled and slowly exchanged pieces, the game reached a QR vs QR position on move 70. Viridithas had a passer on the 6th rank, after 20 moves the passer moved to the 7th rank. Viridithas captured black pawns and reduced to a tablebase win. Revenge won the reverse game.</p><p><a href="https://tcec-chess.com/#div=sw5&game=369&season=25">game 369</a>, <span style="background-color: #04ff00;">Caissa</span> - Ethereal: Ethereal tried to be active against a better white position, it sacrificed a knight for two pawns and created connected passers. Caissa exchanged pawns and created a passer, then traded knight for rook. The engines reduced to a RB vs R ending, Caissa queened first and won. Ethereal won the reverse game.</p><p><i>Standings after 9 double rounds: Caissa Viridithas +2, SmallBrain MrBob +1, Clover StockDory Equisetum Booot Tucano 0, DeepSjeng Weiss BlackCore Winter Stash Expositor -1, Mantissa ChessFighter -2, ice4 -6, 4ku -8, Bagatur -11, OliThink -12. Caissa and Viridithas both beat a close competitor and survived a strong engine, they lead with two double rounds to go. Five engines with medium low rank were lucky to play against low ranking engines and got double wins: Stash, Tucano, StockDory, Equisetum, MrBob. Luck will be an important factor in the last rounds. </i></p><p><a href="https://tcec-chess.com/#div=sw5&game=390&season=25">game 390</a>, <span style="background-color: #04ff00;">Weiss</span> - Expositor: Expositor had a rook and knight stuck on the king side, its king remained uncastled. Weiss attacked through the center, captured 3 pawns and reduced to a won RRB vs RRN position. The reverse game was a draw.</p><p><a href="https://tcec-chess.com/#div=sw5&game=391&season=25">game 391</a>, <span style="background-color: #04ff00;">Stash</span> - StockDory: The engines opened the queen side and both created passers, Stash pinned a bishop on the back rank. Most pieces were exchanged, Stash kept one passer and managed to reduce to a winning king and pawns ending. The reverse game was a draw.</p><p><a href="https://tcec-chess.com/#div=sw5&game=393&season=25">game 393</a>, Equisetum - Booot: The game reached a QN vs Q ending with black two pawns up. Equisetum couldn't find a way to improve, after a long time the game ended in a draw.</p><p><a href="https://tcec-chess.com/#div=sw5&game=396&season=25">game 396</a>, <span style="background-color: #04ff00;">Marvin</span> - Clover: Clover traded its queen for 3 minor pieces, the engines traded pawns and pieces and for a long while it seemed Clover could hold. Clover pushed its last pawn forward, it gave a rook and knight to promote to a queen. This may have been a mistake, Marvin reduced to a R vs BN ending with two pawns up, a 7-man win. The reverse game was a draw.</p><p><a href="https://tcec-chess.com/#div=sw5&game=402&season=25">game 402</a>, <span style="background-color: #04ff00;">SmallBrain</span> - Halogen: The engines opened the king side and both kings were exposed to attack. After many exchanges only RBN vs RBN remained, both king were safe and SmallBrain was up two pawns. The game ended in a tablebase win, the reverse game was a draw.</p><p><a href="https://tcec-chess.com/#div=sw5&game=409&season=25">game 409</a>, <span style="background-color: #04ff00;">Viridithas</span> - Caissa: The game reached a knight ending, material was equal but Viridithas had a protected passer on the 7th rank. Viridithas waited for the right moment, it gave the passer but captured two pawns, enough to win. The reverse game was a draw.</p><p><i>Standings after 10 double rounds: Viridithas +3, SmallBrain +2, Caissa DeepSjeng BlackCore +1, Clover Booot Weiss Tucano Equisetum Stash MrBob Mantissa 0, ChessFighter StockDory -1, Expositor Winter -2, ice4 -8, 4ku -9, Bagatur -13, OliThink -14. Viridithas took the lead with a win against Caissa, SmallBrain is in second place after a win against Halogen. DeepSjeng and BlackCore used their double wins against low ranking engines to climb back to the top, Mantissa was also lucky to get a double win.</i></p><p><i>Expositor and MrBob both won twice against low ranking engines, Winter only managed one win and ChessFighter only drew against ice4. </i></p><p><a href="https://tcec-chess.com/#div=sw5&game=432&season=25">game 432</a>, <span style="background-color: #04ff00;">Equisetum</span> - Mantissa: Equisetum created a passer in a closed position. When the queen side opened Equisetum captured a pawn and reduced to a QRN vs QRN position. It pushed a second passer forward and captured another pawn, Mantissa lost more material and was eventually mated. The reverse game was a draw.</p><p><a href="https://tcec-chess.com/#div=sw5&game=435&season=25">game 435</a>, <span style="background-color: #04ff00;">Clover</span> - Booot: Both engines had passers, Clover protected its passer better. Booot lost one passer and pushed the other to the 2nd rank, in a QRB vs QRB position Clover captured a pawn and created a second passer. Booot lost its rook for the white passers, game over. In the reverse game Booot had a chance to win but it reduced to a drawn Q vs RN ending. </p><p><a href="https://tcec-chess.com/#div=sw5&game=432&season=25">game 437</a>, <span style="background-color: #04ff00;">Weiss</span> - Marvin: The game reached a QRB vs QRB position, Weiss gave two pawns and used a back rank pin to reduce to a R vs B ending. It took almost 100 more moves to get to a tablebase win. The reverse game was a draw.</p><p><a href="https://tcec-chess.com/#div=sw5&game=446&season=25">game 446</a>, <span style="background-color: #04ff00;">Seer</span> - DeepSjeng: Seer captured a rook for a bishop and pawn, the game reached R vs N ending with black two pawns up. DeepSjeng pushed two passers forward, Seer gave the rook to stop them but DeepSjeng couldn't stop an advanced white passer, game over. In the reverse game DeepSjeng had an advantage in a BB vs BN position but couldn't convert to a win. </p><p><a href="https://tcec-chess.com/#div=sw5&game=447&season=25">game 447</a>, <span style="background-color: #04ff00;">Caissa</span> - Arasan: The engines gradually exchanged pieces, with the white eval advantage increasing. The game reached a rook ending with white a pawn up, this was enough for Caissa to win. Arasan won the reverse game. </p><p><i>SmallBrain and Viridithas lost to strong engines. Viridithas finished first, tied with MrBob (!!!) at +2, followed by Caissa, SmallBrain, Weiss, Equisetum and Clover at +1.</i></p><p><i><br /></i></p>Assaf Woolhttp://www.blogger.com/profile/16213029778243498981noreply@blogger.com0