SEVILLE, SPAIN, DEC. 14 -- Anatoly Karpov used his last timeout today to postpone the final showdown with Gary Kasparov in the world chess championship.

The 23rd game of the 24-game series was rescheduled for Wednesday, with challenger Karpov having the advantage of the white pieces.

The match is tied at 11-11, with three wins and 16 draws for each player. If the series ends at 12-12, Kasparov, 24, will retain the title.

Most experts had expected Karpov's timeout because it is essential for him to launch a well-prepared assault in his final game with the advantage of the first move. Karpov, 36, has appeared to be the calmer of the two players during the final phase of the 10-week war of nerves.

Nevertheless, in addition to Kasparov's advantage of needing only two draws to retain the crown, he has always managed to rise to the occasion in the past. Kasparov beat back an eleventh-hour attack by Karpov in the final game of their 1985 match in Moscow to win the world title, 13-11.

Their 1986 encounter also ended in Kasparov's favor after he won the 22nd game to retain his title by a single point, having earlier frittered away a three-point advantage.