The world of chess has been rocked by a controversial demand for the game's greatest international tournament to be played in complete silence.
By Matthew Day in Warsaw
Bulgarian champion Veselin Topalov has invoked little-known rules which allow him to ban conversation between the him and his opponent during the World Chess Championship.
Casting aside the sport's staid and cerebral reputation, he has insisted he will not speak to India's Viswanathan Anand as they compete for the title and a prize of £1.7 million over almost a month.
Rules allowing players to demand a ban on communication were introduced in 2005 in order to curb the practice of competitors offering each other draws during drawn-out games.
But they have rarely been invoked and this is the first time any player has demanded their application in a world championship.
The move by Topalov, who has a reputation as the "bad boy" of chess, have been described as "insane" and "a sheer provocation".
The dispute has been escalated by Anand, a popular figure on the world chess scene, who has said he will refuse to play in silence, arguing "a world championship should be played with world championship rules."
His refusal prompted Mr Danailov to accuse the Indian and his camp of disrespect.
Silvio Danailov, the Bulgarian's manager, said his man would refuse to communicate with his opponent during the tournament even if spoken to.
"If Vishy [Mr Anand] doesn't agree to the rules he will be forced to, because Topalov will not offer him a draw and he will not speak to him," he said.
"In our personal opinion they show no respect to the organisers, the sponsors and the city of Sofia.
"Veselin in general doesn't like to be disturbed by talks and draw offers during the game. What is the problem here? Why do you call this provocation?"
The prospect of a silent world championship has caused a stir in golf's usual placid waters.
Arne Moll, columnist for website Chessvibes, said: "The most remarkable thing is that Danailov says that Topalov will not only refuse to offer any draws but also will ignore his opponent altogether.
"In other words, he will drop all courtesy and normal etiquette and create a 'non-speaking terms' atmosphere in a match in his home country, against one of the most relaxed and friendly chess players on the professional chess scene."
It is not the first time Mr Topalov has found himself embroiled on controversy during tournaments.
During the 2006 world championship, he scandalised the chess world when he accused Vladimir Kramnik, his Russian opponent, of cheating while in the lavatory.
In what became known as "Toiletgate", Mr Topalov claimed that the Russian had somehow managed, while inside the loo, to break strict rules prohibiting any communication with the outside world and get advice on what move to make next. Infuriated by the allegations Mr Kramnik, refused to play one match before going on to win the tournament.