Challenger Anatoly Karpov, trailing champion Gary Kasparov by a point in the World Chess Championship match in Lyon, France, was granted a postponement of Game 19 yesterday. Each player is allowed three postponements in the 24-game match, and each now has one left.

Karpov had tried to get a technical timeout for the conclusion of Game 18 because of heavy snow on Sunday, without using part of his quota, but this was not allowed by chief arbiter Geurt Gijssen, who drove out to Karpov's residence and brought him in to play. Karpov went on to lose that game. Yesterday's request was charged against Karpov's quota, but he did not have to cite a reason. It was phoned in to Gijssen 10 minutes before the noon deadline.

The timeout gives Karpov two days to rest and prepare for the crucial final quarter of the match. He has been one point behind twice before and has come back to even the score both times. Kasparov's victory Sunday was his third. Previously, he had won games 2 and 16, and Karpov had evened the score with wins in games 7 and 17. Karpov will have the white pieces and the first move in Game 19, now scheduled to start tomorrow.

All five victories so far have gone to the player with white, but even if Karpov wins tomorrow he will still face an uphill struggle in the five remaining games. If the score is tied at 12-12, the $3 million prize fund will be divided evenly, but Kasparov will remain world champion. Otherwise, the title and a $1.7 million first prize will go to the first player who scores 12 1/2 points.