After 60 games Stockfish leads 20-11 with 29 draws. Stockfish won 3 more game pairs and extended its lead to 9 wins. There were two more game pairs with two white wins in the last 5 pairs. Leela hasn't won a game pair in the last 11, since there are only 20 game pairs left in the match it is safe to assume that Stockfish is going to win.
Games 51-52 started with the Queen's pawn game, Krause variation. The c file was open, the black queen was out on the queen side and the black king side pieces were not developed. In game 51 both engines developed their pieces and castled their kings. The engines played out a long PV agreement, Leela gave a pawn and opened the e file, then its queen moved forward and captured a pawn on the queen side. Leela's eval jumped for a few moves and came back down. The engines exchanged a pair of rooks and Leela captured another pawn on the queen side, creating connected passers. The game reached a RN vs RB position, Stockfish's eval was at 0 but Leela's eval wouldn't come down. Stockfish captured one passer, the other reached the 6th rank. Leela saw the draw and the game was adjudicated.
In game 52 the engines developed their pieces and castled but with some changes compared to game 51. The engines traded bishops, Leela captured a pawn on the queen side and created a pawn majority, while Stockfish captured a pawn on the king side and weakened the black king's pawn support. Leela moved rooks to the g file to protect its king, the engines mostly shuffled for a while with stable evals. Stockfish pushed the d pawn and it became a passer. Evals started to increase after move 47, Leela pushed pawns on the queen side and Stockfish pushed the passer to d6.
Stockfish captured one pawn on the queen side, the game reached a QRR vs QRR position and the engines cleared the queen side pawns. Leela captured a pawn on the king side and equalized material, the engines exchanged queens and each had two pawns left. Stockfish managed to move its rooks to the open h file with its passer unharmed. It chased the black king forward to the center and captured a pawn, it saw the win in its PV.
Stockfish moved its rooks to the 6th rank, then pushed the passer forward. Leela exchanged rooks and the game ended in a tablebase win. Stockfish wins the game pair, it leads 16-9.
Games 53-54 started with a 20-ply line in the Vienna game, Anderssen defense. There was one pawn exchange on the king side, black pushed pawns on the queen side, all pieces were on the board and both kings were still uncastled. In game 53 there was one minor piece exchange and the engines castled in opposite directions. Another minor piece exchange locked the queen side, Stockfish had a bishop pair but with so many pawns the white knights were better. The engines shuffled for a while, they locked the king side and shuffled some more. On move 47 Leela captured a pawn on the queen side and created a passer, Stockfish moved a bishop forward and used it to complete a pawn wall. There was a very long shuffle and evals drifted down, on move 104 Leela opened the a file and the engines started to exchange pieces. The game wad adjudicated a few moves later.
In game 54 the engines exchanged minor pieces and opened the e file, then castled in opposite directions. Leela's eval was quite low, around 0.5, while Stockfish eval increased. Stockfish gave a bishop for a pawn and captured a rook for a knight, on move 26 its eval jumped over 3 while Leela's eval was still under 1.
Leela's eval finally reacted, Stockfish gave a rook for a knight and attacked the black king. The engines played out a long PV agreement, the game reached a QR vs QR position and the center pawns were cleared. Stockfish's pieces controlled the center, on move 43 Stockfish captured the a pawn and exchanged rooks.
Leela avoided exchanging queens, Stockfish used this to keep the black queen away and slowly pushed the a passer. Leela captured a pawn but Stockfish queened the passer and mated. Stockfish wins the game pair, it leads 17-9.
Games 55-56 started with a sideline in the Nimzo-Indian defense, Saemisch accelerated variation. All pawns were on the board, there was one minor piece exchange, all white pieces were undeveloped. In game 55 the engines exchanged pawns in the center and a pair of bishops, the white king moved without castling. Stockfish castled its king, Leela did the same by moving the rook and the king. Leela's eval started to increase, it created a passer in the center and pushed the h pawn. Most of the black pieces were passive, Leela slowly prepared its king side attack.
On move 40 Leela checked with its knight on g6, Stockfish exchanged knights and a white pawn landed on g6. Stockfish captured a pawn while Leela pushed the passer to e7. Leela drove the black queen away, Stockfish in desperation preferred to take the passer and gave its queen. Leela gave some material back and found a quick way to mate.
In game 56 the engines repeated game 55 for 14 plys with transposition, the white king moved without castling after exchanging bishops. The engines castled exactly as before, Stockfish created a passer in the center and pushed it to the 6th rank, its eval increasing. Stockfish gave a pawn on the king side, Leela refused two offers of another pawn to keep the g file safe, as a result it pushed a pawn to g3 without support.
After exchanging minor pieces Stockfish moved a rook forward and captured the g3 pawn. Leela could take the h5 knight but avoided opening the g file. Stockfish doubled rooks on the g file, then captured a rook for a knight. Leela captured the white passer while the white queen moved forward on the king side. Stockfish shifted its rooks to the e file and exchanged queens.
Stockfish used the fact that the black pieces couldn't move without losing material, it pushed pawns on the king side and forced the king to move. The engines reduced to a rook vs pawns endgame, Leela was 4 pawns up but they were no match for the white rook. The game ended in a tablebase win. There were two white wins in this pair, Stockfish leads 18-10.
Games 57-58 started with a 26-ply sideline in the Ruy Lopez, closed, Flohr system, rare in human chess. All pieces and pawns were on the board. In game 57 Leela locked the center, a pawn exchange opened the b file. Leela captured a pawn and the engines mostly shuffled for a while. Stockfish regained the pawn and the first piece exchange was on move 36. Evals started to come down, the engines exchanged pieces and the game reached a QRR vs QRB position with black a pawn up. The engines continued to exchange pieces and pawns and the game was adjudicated.
In game 58 Stockfish locked the center like in game 57, this time a pawn exchange on the queen side created a passer for Leela and the b file remained closed. Evals started to increase, on move 31 a few exchanges on the queen side created a white passer in the center and opened the a file where Stockfish had doubled rooks.
Leela gave a pawn, a minor piece exchange opened the h file. Stockfish gave a rook for a bishop and pawn and the black king was exposed. The game reached a QRB vs QRR position with white two pawns up on move 48.
The engines exchanged a pair of rooks and traded pawns, Stockfish captured another pawn and created a second passer on the queen side. It pushed the d passer to d7 where Leela captured it and Stockfish captured the g pawn, creating a passer on the king side. After exchanging queens Leela lost its last pawn, Stockfish queened a passer and the game ended in a tablebase win. Stockfish wins the game pair, it leads 19-10.
Games 59-60 started with a 22-ply line in the KID Fianchetto variation, played in high level human chess. The center was locked and all pieces and pawns were on the board. In game 59 evals increased steadily from the start. There was one minor piece exchange on the king side, then Leela doubled rooks on the b file and exchanged knights and pawns there. The a file opened, Stockfish also doubled rooks on the b file to protect its b6 pawn. After another minor piece exchange Leela had more attackers and it captured the b6 pawn. In a series of exchanges Leela gave a pawn and the engines reduced to a RB vs RB position.
Leela captured the c pawn and focused on its d passer. Stockfish moved its rook to the 2nd rank to control the white king as a counter. Stockfish captured a pawn on the king side, then moved its rook to the d file so the white passer will not move. This let the white king move forward to support the passer. Stockfish captured two pawns while Leela pushed the passer to d7. Stockfish gave the rook for a bishop, Leela was on time to stop any black passer and the game ended in a tablebase win.
In game 60 all pieces stayed on the board, there was one pawn exchange on the queen side that let the black queen side rook have some room to move. All the rooks moved to the a file and the engines shuffled for a while. For a few moves Leela's eval dropped, then it came back again, Stockfish's eval increased slowly. Stockfish cleared the 2nd rank and moved its rooks to the king side, on move 41 it exchanged pawns and opened the g file. The engines exchanged a pair of rooks and minor pieces, the h file opened and both kings were exposed.
The black pieces were passive, defending the black king and pawns and each other. Leela moved the knight on the queen side to join the defense, after Stockfish gave a pawn its bishop moved forward and landed on e6. Leela tried to counter with a passer on the queen side, with the black queen supporting. Stockfish gave a rook for a knight and attacked the black king, which ran to the queen side. Leela lost more material and was mated. There were two white wins in this pair, Stockfish leads 20-11.
No comments:
Post a Comment