World No 1 chess player Garry Kasparov was held to a draw on Tuesday in the first game of his latest match against 'X3D Fritz' computer.
Kasparov and the programmers of 'X3D Fritz' agreed to a draw on the 37th move after three hours and 20 minutes of play in a hard-fought game in which the Russian won a rook in exchange for a bishop and a pawn in the middlegame.
The grandmaster played the programme without physically moving chess pieces on a board or pressing the button of a chess clock.
"The position was not easy technically. I think I missed a chance to consolidate my position," said the former world champion, who played with the white pieces.
"I was worrying a lot about the screen," Kasparov, 40, said. "I knew before this match that I could have some psychological problems with this technology."
The second game of the four-game match at the New York Athletic Club was set for Thursday. The games were being broadcast on Web sites and on the cable TV sports channel ESPN2.
One point is awarded for a win and a half point for a draw. The prize is $200,000 for the winner and $175,000 if the match ends in a tie.
The machine is German-made Fritz software, dominant in computer chess and sold commercially, combined with New York-based X3D Technologies company software that specialises in virtual reality.
In February, Kasparov tied his last match against a programme, the Israeli-designed world computer chess champion Deep Junior.
The Azerbaijan-born Kasparov's quest to conquer chess-playing machines drew worldwide attention in 1996 and 1997 when he played IBM supercomputer Deep Blue, which has since been retired.
Kasparov, considered one of the greatest players in the history of the game, is still ranked No 1 ahead of world champion Vladimir Kramnik of Russia by the International Chess Federation.