Challenger Anatoly Karpov outmaneuvered world chess champion Gary Kasparov on Wednesday to win the 17th game of their 24-game title match and keep alive his chances of recapturing the chess crown.
Karpov's win closed the champion's lead to two points, 9 1/2 to 7 1/2, but Kasparov needs only five draws from the seven remaining games to keep the title he seized from Karpov last November.
Kasparov, playing black, made what expert observers deemed the serious error of repeating an opening variation he used to take an easy draw in the 15th game.
Karpov was eventually a pawn ahead, and Kasparov resigned after his opponent played his 31st move.
Karpov opened with a Gruenfeld Defense. He unveiled a new move at move 14, sacrificing a pawn to leave Kasparov with weak, doubled queen's bishop pawns.
When Karpov penetrated black's position with a rook at move 23, international chess master Yevgeny Vladimirov called the challenger's chances "completely hopeless."
But at move 24, Karpov picked up one of Kasparov's weak queen's bishop pawns. Two moves later, he took the other, leaving himself a pawn ahead.
The winner of the match will be the first player to score six victories or 12 1/2 points. If there is a 12-12 tie, Kasparov remains champion.
Kasparov has won four games and Karpov two.
Each victory counts a point, and in the event of a a draw, both players are awarded half a point.
Here are the moves:
Karpov-Kasparov 17: 1 d4 Nf6 2 c4 g6 3 Nc3 d5 4 Nf3 Bg7 5 Qb3 dxc4 6 Qxc4 0-0 7 e4 Bg4 8 Be3 Nfd7 9 Rd1 Nc6 10 Be2 Nb6 11 Qc5 Qd6 12 e5 Qxc5 13 dxc5 Nc8 14 h3 Bxf3 15 Bxf3 Bxe5 16 Bxc6 Bxc6 17 Bd4 Bf4 18 0-0 a5 19 Rfe1 a4 20 Re4 Bh6 21 Be5 a3 22 b3 Na7 23 Rd7 Bc1 24 Rxc7 Bb2 25 Na4 Nb5 26 Rxc6 Rfd8 27 Rb6 Rd5 28 Bg3 Nc3 29 Nxc3 Bxc3 30 C6 Bd4 31 Rb7 Black resigns