World chess champion Gary Kasparov and challenger Anatoly Karpov played to a draw in Game 8 of the World Chess Championship in New York yesterday, adding to their score the hardest-earned half-points of the match so far.

The game was adjourned on Monday after 40 moves and five hours of play. Its second segment was longer than the beginning, with 44 additional moves that took more than five hours to complete.

After one-third of its prescribed 24-game maximum, the match is tied with a score of 4 to 4: one victory for each player and six draws. Compared with the free-wheeling first session, which featured complex combinations and massive exchanges of material, the continuation was an endgame -- subtle and relatively quiet, more interesting to connoisseurs than to casual fans until it became obvious that it was a draw and both players were simply acting stubborn.

Only one pawn was captured in the whole session until the exchange of queens on Move 79, and perhaps most crucial in determining the outcome was the fact that Karpov had to capture the bishop on d5 with a pawn, splitting his two linked passed pawns and making them much less effective in the endgame. Obviously, he could not have played 41. ... Qxd5 because of 42. Qxc6, mate. Another fatal mistake would be 41. ... Rxd5 because of 42. Qg4 with an unstoppable mate either on g7 or on g8.

In the early stages, Karpov tried a few tricks such as 47. ... Re4, tempting white to play 48. Qxe4, which he would have refuted with Qc7ch, winning the queen.

Eventually, taking advantage of the black king's relatively insecure position, Kasparov was able to block his opponent's divided pawns. Karpov managed to move a pawn to d4 but, to advance it further, he had to give up his b-pawn. Kasparov was even able to offer a rook endgame with 64. Qa1 because his king would quickly come to destroy black's d-pawn.

Karpov's last try, 69. ...Ra4, was parried by 70. Re1. Kasparov could not take the d-pawn with 70. Rxd3 because of Ra1ch.

Karpov's 70. ... h5 was a result of time pressure and gave Kasparov a handy target. After 73. Qd2ch, Kasparov could have forced a draw by repetition if he chose. He did not choose, and tried to exploit the weak square g6. Karpov had to play 74. ... h4 to defend against the deadly 75. Qg3ch, but after that, neither side could play for a win. The fact that the game went for another 10 moves is a tribute to the players' obstinacy, not to their analytic powers.

It was the second-longest game the two had ever played, and they stayed to analyze it together after they had called it a draw.

Game 9 is scheduled to begin tonight with Karpov playing white.

Lubomir Kavalek is a chess grandmaster. Joseph McLellan is a Washington Post staff writer.