The match for the world chess championship taking place in Elista, the capital of the Russian republic of Kalmykia, took a bizarre turn yesterday as one side — unsurprisingly, the player who is trailing — accused the other of suspicious behavior during the games and threatened to quit.

On a day in which no game was played, Silvio Danailov, the manager of Veselin Topalov of Bulgaria, sent a letter to the appeals committee of the match detailing what he said were an excessive number of bathroom breaks — more than 50 per game — by Vladimir Kramnik of Russia. (The length of the games varied from less than four hours to more than six.)

The letter stopped short of accusing Mr. Kramnik of cheating, presumably by getting the assistance of a computer, but it noted that there was no surveillance equipment in the private bathrooms used by the players, and it demanded that both players be required to use a public restroom from now on, and then only when accompanied by a match referee.

The letter, which was sent to several journalists, concluded by saying that Mr. Topalov might withdraw from the match if the demands were not met. An appeals committee will review the protest, and presumably will take it seriously to avoid having the match derailed.