Season 21 league 1 after RR2

Standings after RR2

Igel has a promising lead after RR2, 2 points ahead of its nearest rivals. A group of 3 engines is currently tied for 2nd place.

Currently rofChade and Xiphos are at the bottom, Nemorino and SlowChess are also in danger of relegation. 

Only Igel is unbeaten so far, all other engines have at least one win and one loss. A lot more can still happen, there are 14 more rounds to play.

The openings for league 1 were created by Bastiaan Braams. They are biased, but not extremely so. So far there has been only one opening with wins for both engines, and the draw rate is more than 65%. In season 20 the openings in league 1, also by Bastiaan Braams, were so biased that the expected result was a white win and standings were determined by the number of draws playing black.

Interesting games

game 2, Ethereal - Xiphos: Ethereal had an eval advantage from the start, its eval was over 1 for a long while with only a few pawn exchanges. On move 31 the engines started to exchange pieces and the game reached a RB vs BN position, Ethereal's eval was close to 4. After 30 more moves the game ended in a tablebase win.

game 6, rofChade - SlowChess: SlowChess gave a pawn early, but did not get enough compensation for it. It gave a second pawn and tried to attack the white king, rofChade exchanged pieces and was never in real danger. The game reached a BN vs R position, rofChade had an advanced passer and SlowChess was forced to give a rook for a knight to stop it. rofChade was left with enough material to win.

game 10, Igel - Pedone: The game reached an opposite color bishop ending with Igel two pawns up. Pedone blundered after a long shuffle, allowing Igel to capture two more pawns and win.

game 11, SlowChess - Xiphos: SlowChess had a bishop pair advantage, the game reached a RBB vs RNN position. The bishops were strong in the open board, SlowChess went two pawns up before trading a bishop for a knight. Xiphos had to give its rook to stop a white passer, game over.

game 15, Pedone - SlowChess: SlowChess traded a knight for two pawns at the start, then captured a 3rd pawn. Pedone captured a pawn and created a passer, evals started to climb. The engines reduced to a RN vs R position, Pedone captured pawns and pushed its passer forward. SlowChess captured the passer but Pedone had enough pawns to win.

game 17, Igel - RubiChess: The center and queen side were blocked, the engines mostly shuffled for 30 moves with a few piece exchanges. On move 66 Igel opened a file in the center and traded a knight for a rook. It then gave the material back to create an advanced passer in the center. RubiChess was up a pawn in a QR vs QR position, but when Igel connected a second passer the threat became too great. RubiChess lost material to stop the passers and got mated.

game 26, Nemorino - Igel: Igel was a pawn up with a queen side passer and evals were around 2. After playing out long PV agreements evals came down and the game reduced to a QRB vs QRN position. Nemorino managed to remove the advancing black passer and exchange queens, leading to a drawn tablebase position.

Standings after 7 rounds: Igel +3, Ethereal Pedone +2 Nemorino +1, RubiChess 0, SlowChess -1, Xiphos -3, rofChade -4.

game 29, RubiChess - Pedone: Pedone went a pawn up but its king was uncastled in the center and its DS bishop was trapped and undeveloped. RubiChess placed a knight on d5 and opened the queen side. By the time Pedone freed its bishop RubiChess was a pawn up with a central passer. Pedone lost material fast and was mated.

game 30, Xiphos - Ethereal: After a series of exchanges Xiphos was a pawn up, all the pawns on the queen side were cleared besides one white passer.The engines shuffled for a while, then Ethereal exchanged minor pieces and evals jumped. Only QRR vs QRR remained, Xiphos slowly pushed the passer forward and Ethereal couldn't stop it. Xiphos captured all the black pawns and queened to win. There were two white wins in this opening.

game 42, Nemorino - Xiphos: Nemorino had an eval advantage from the start, the center was blocked and the black king was uncastled in the center. After some shuffling and minor pieces exchanges Nemorino opened the king side and both engines had passers. Evals came down and then became negative as both passers were captured and only QRN vs QRN remained. The white king was in the corner on the queen side, Xiphos threatened the back ranks with its major pieces and it went two pawns up. It took some time but the material advantage was enough for Xiphos to reach a wining knight ending. 

game 44, Igel - Ethereal: Igel went up a pawn after the start, Ethereal traded both its bishops for knights and captured a pawn back. Igel pushed pawns on the king side and drove the black pieces back. After exchanging queens the white bishops found strong outposts that restricted the black pieces. Igel attacked through the queen side and reduced to a B vs N ending with a pawn up. The black knight was trapped in the corner and Ethereal was in zugzwang. Igel was able to queen a pawn and win.

game 51, Nemorino - Ethereal: Nemorino had an eval around 1 from the start, the position was closed and there were only a few exchanges. After a long shuffle Ethereal gave a pawn to open the center and created a passer on the 3rd rank. Evals became negative and climbed quickly, the engines reduced to a QBN vs QNN position. The white king was under threat on the back rank and Nemorino gave a knight to remove the passer. After exchanging queens Ethereal went a pawn up in a B vs NN position. It created an unstoppable passer that ensured the win.

game 54, Igel - Nemorino: The game reached a R vs RN position, with 3 white pawns and 2 black pawns. (Negative) evals were high and it appears that Nemorino could have won. However it played the wrong move and evals dropped to 0. Igel found a way to get rid of the black pawns and Nemorino didn't have the material to win.