Since losing in the fourth round at Wimbledon to Marcos Baghdatis, Davydenko lost three straight first-round matches — to Gael Monfils at the Swiss Open, Florent Serra at the Dutch Open and Gilles Simon at the Croatia Open — before beating Andrei Pavel, 6-3, 6-4 in the opening round in Poland.

Arguello lost 2-6, 6-4, 6-2 on Friday in the quarterfinals to another Argentine player, Jose Acasuso.

“I saw Davydenko playing very well the first set, and I saw also that he had problems with his feet, and that was true, he was not inventing that, so it’s difficult to suspect him,” Arguello told The Associated Press by telephone from his hotel room in Sopot.

Fellow Russian Marat Safin, playing this week in Washington, declined to speculate about the Davydenko situation.

“I don’t really care,” Safin said. “Whatever people do, and whatever they want to do, I don’t care. I just want to play my matches and enjoy my time. I’ve enough problems myself.”

At Wimbledon in 2006, Betfair reported irregular patterns surrounding a first-round match between British wild card Richard Bloomfield and Carlos Berlocq of Argentina.

Berlocq, who was ranked 170 places higher than Bloomfield, lost 6-1, 6-2, 6-2. Most of the bets placed were on Berlocq to lose. However, no wrongdoing was detected.

Allegations of match-fixing in tennis have cropped up in the past.

In 2003, bookmakers reportedly suspended betting six hours before Russian player Yevgeny Kafelnikov’s match in Lyon, France, against Fernando Vicente after a big wager was place on the Spaniard. Vicente, who had been winless for several months, won in straight sets. There was no suggestion either player was involved in wrongdoing, and no investigation was made by the ATP.

Several Russian tennis players were photographed a few years ago with Alimzhan Tokhtakhounov, a suspected mobster from the former Soviet republic of Uzbekistan who was accused of fixing the pairs and ice dancing events at the 2002 Salt Lake City Olympics.

Photographs of Tokhtakhounov with Kafelnikov, Safin and Andrei Medvedev were taken off Medvedev’s Web site in 2002 after the man’s arrest. Tokhtakhounov spent nearly a year in a Venice, Italy, prison but escaped extradition to the United States in 2003 on the Olympic rigging charges.

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