Game 17 of the World Chess Championship was summed up succinctly by one commentator at the Teatro Lope de Vega in Seville, Spain. "Karpov squeezed with all his might, but it was a very dry lemon," said Canadian chess master Nathan Divinsky after the adjourned game ended yesterday in a 46-move draw.

The time indeed has come for challenger Anatoly Karpov to squeeze hard and keep squeezing if he hopes to wrench the title from defending champion Gary Kasparov. The match score stands at 8 1/2 points for each player with only seven games remaining in the 24-game match. Kasparov remains champion if the match ends in a 12-12 deadlock, and each draw (worth a half point) moves him one small step closer to that result.

For Karpov, the strategy now seems relatively simple: He must win at least one more game. Accordingly, he turned down a draw Wednesday, although the position looked unpromising, and he came back for nearly an hour yesterday to play four more probing moves after the adjournment. Kasparov faces more complicated decisions. Theoretically, he can sit tight, turn back attacks and hope to coast into safety until the next championship match, three years from now, by drawing the remaining seven games. But that means depending on the slimmest of possible margins, and he cannot be completely sure of playing seven draws in a row. Playing to win inevitably means taking chances, but they cannot be entirely avoided even by playing to draw.

There is also the matter of pride. Kasparov does not want to remain champion merely by not losing; his public statements and observed behavior both testify that he wants to destroy his opponent. Many factors are combining to lure him out of a defensive posture, and Karpov can be expected to add to the tension by dropping bits of bait in front of him.

As he sits down to each of the four remaining games in which he plays white, beginning with Game 18 today, there will be a debate raging in Kasparov's mind: to play it safe or to go for blood.

After yesterday's game, the two players stayed at the board for a few minutes of postmortem analysis -- the first time they have done so in this match. Observers said that Kasparov was the one who broke the ice. They also reported that the champion seemed tense when he came in.

Kasparov arrived 10 minutes late to resume the adjourned game -- possibly an implied rebuke to Karpov, who has habitually arrived a few minutes late each day. Observers have said Karpov's tardiness was aimed at upsetting the champion, who loses time on his clock because he refuses to start until his opponent's arrival. But when Karpov arrived on time for the start of Game 17, that was also interpreted as an attempt to upset Kasparov.