Game 13 of the World Chess Championship was declared a draw yesterday, as expected. The agreement was reached by telephone, without either challenger Anatoly Karpov or defending champion Gary Kasparov bothering to return to the 900-seat auditorium in the Palais des Congres, overlooking the Rhone River in Lyon, France.

The move sealed by Karpov at the adjournment Saturday was (also as expected) 42. Kxd3. This was the beginning of a sequence that would have led to a virtually forced draw: 42. Kxd3, Rxa4; 43. d6, Ra1; 44. Kc2, Ra4; 45. Kd3. The black rook cannot occupy the d-file, attacking the white passed pawn, and black has to repeat the moves, leading to a draw after the same position is reached three times, to keep white from advancing his d-pawn.

This is the 11th draw played so far in the 24-game match. With one victory for each of the players, the score is tied with 6 1/2 points apiece. The first player to gain 12 1/2 points wins the championship and $1.7 million of a $3 million purse. If he reaches 12 points, assuring at least a 12-12 tie, Kasparov keeps his title. Games are played three times per week, and with two timeouts still permitted for each player the match could last until the end of December.

Although it ended in a draw, Game 13 was not the kind of placid exhibition sometimes called a "grandmaster draw." From beginning to end, it was an intense struggle for the initiative and for control of space, with both players taking calculated risks and a finale that required close calculation and precise timing. As it has been in many games of this match, a major motif was the exchange sacrifice, in which a player swaps a major piece (usually a rook, occasionally a queen) for one of lesser value (usually a bishop or knight, occasionally a pawn). An unusually elegant pair of exchange sacrifices took place in Moves 20-22 (20.Rxc3, Bxc3; 21.Ne4, Rxe4; 22.Bxe4). Exchange sacrifices are more typical of Kasparov's style than of Karpov's, but Karpov had to initiate the exchange of exchanges in this game. First, to keep Karpov from centralizing his knight on e4, Kasparov played 19. ... Nc3. Karpov immediately sacrificed the exchange to allow the knight move anyway, and this forced Kasparov to give the exchange back. It would have been dangerous for Kasparov to play 21. ... Be5, because of the sequence 22. Nxc5, Bc8; 23. Rd1, with strong pressure for white.

Earlier, Kasparov emerged from the opening with more freedom for his pieces (especially the bishops) than Karpov had. By Move 11, Karpov had created a passed pawn, but black was in a good position to blockade it. With 15. ... Nb6, Kasparov was ready to jump his knight to a4, forcing the exchange of queens, but after 16. g4, Be4 would play into Karpov's hands: 17. c4, Qxd2; 18. Nxd2, and the bishop on e4 would be in an uncomfortable position. After the exchange of white-squared bishops, Kasparov had a strong position unusual in an endgame with a player's pawns on squares of the same color as his bishop. With 31. ... Bc7, it began to be clear that Karpov would be pushed back. After 35 moves, Karpov had only five minutes for his remaining five moves. With 40. Ke1, he was able to avoid a brilliant tactical stroke prepared by Kasparov. Had he played the tempting 40. d6, Kasparov would have won with a rook sacrifice. 40. ... Rg1ch; 41. Kxg1, d2, and the pawn cannot be stopped from queening.

In a press conference held the day before the match opened its second phase in Lyon, Kasparov said that in order to win he would have to play better than he had in New York; Karpov said he would have to play better than Kasparov. Karpov did not manage that in the first game played in Lyon, and Kasparov managed only in a limited sense: He played the Gruenfeld Indian defense better than he had on the one occasion he used it in New York. Evidently the champion was unhappy with the results he obtained from the King's Indian defense in the New York half of the match, and the Gruenfeld will probably be his main resource with black for the remaining games.

During the intermission between the New York and Lyon phases, Kasparov said he had played a lot of tennis and Karpov said he had slept a lot. Both obviously spent much time studying their openings, particularly their defenses, with results that will become clear in the games ahead.

Game 14 is scheduled for today with Kasparov playing white.

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