NEW YORK: Garry Kasparov was held to a draw by the chess-playing computer Deep Junior after the software program made a speculative bishop sacrifice in Wednesday's fifth game of their six-game match in New York.

The match is tied at 2-1/2 points each with everything to play for in Friday's final game of the contest billed the International Chess Federation's Man vs. Machine world championship.

"The last game is very difficult for a human. It is a great burden on my shoulders," said Kasparov, who holds the world No. 1 ranking. He famously lost a match to the IBM supercomputer Deep Blue six years ago and is in the identical situation after Wednesday's game. "I hope I can do better than in '97," he said.

The Russian grandmaster, playing with the white pieces and having the advantage of the first move, and Deep Junior opened relatively quietly. But on the computer's 10th turn, it gave up a bishop for a pawn in what chess experts watching the game at the New York Athletic Club described as an unusually speculative attack on the king by a machine.

Kasparov's king was sent scurrying up the board and, in a defensive posture, the former world champion decided to take a less risky course that resulted in the position being repeated three times, which is a draw under the rules of chess. Only 19 moves had been played in 90 minutes at the board.

The Israeli programmers of Deep Junior, a software program that can run on a general purpose PC and calculates 3 million positions a second, said the computer's analysis showed Kasparov had made the best choice.

Kasparov, as he vowed six years ago, has thrown out his cautious "anti-computer" strategy for bold, aggressive formations.

© Reuters