Nikolay Davydenko said an on-court conversation with his wife Irina may have accidentally triggered the betting scandal which has plagued him since last year.

The Russian world number four's match against Argentine Martin Vassallo Arguello in Sopot, Poland on August 2 2007 is under investigation by the sport's governing body after British online company Betfair reported irregular betting patterns.

• Davydenko warned for not trying

Betfair voided all bets on the match, from which Davydenko retired hurt with a foot injury, and reported it to the ATP.

While both players have denied any wrongdoing, Davydenko had his own theory about how the betting patterns on the match could have suddenly shifted in the lowly-ranked Argentine's favour.

"I spoke on the centre court with my wife in Russian [and] maybe it's possible, I say something [like], 'I don't want to play or I can retire'," Davydenko said after losing 6-4, 6-4, 6-4 to Germany's [Images] Benjamin Becker in the first round at Wimbledon on Tuesday.

"Because we play in Sopot and many Russians are watching the match... some people can understand. It may be my mistake because I need to be quiet, I need to do only my job."

PHONE RECORDS

The 27-year-old added he had submitted all the information requested by the investigators, including his and his wife's phone records. However, he was unable to hand over his brother's records as they were not available.

Despite the ordeal which has lasted almost 11 months, Davydenko remains confident he would be able to clear his name.

"I know from my lawyer it should be decided in July," he said.

• Wimbledon plays down fixing allegations

"Nobody can prove anything. Because if [they] found something about me, [they would] have already told me, or my lawyer. He's already waiting mostly like one year and didn't find anything."

Davydenko, who described his ordeal as a "bad dream", said he does not think there is any match-fixing in tennis.

However, should any player be caught corrupting the sport, he has no hesitation in suggesting what the punishment should be.

"I think they should be disqualified [banned]. It is the biggest penalty the ATP can give," he said.

Last month a probe found that while professional tennis was "neither systematically nor institutionally corrupt", 45 professional matches in the past five years had unusual betting patterns and required further investigation.

Tennis authorities, including the four Grand Slams, the ATP and WTA tours and the International Tennis Federation have agreed to set up an integrity unit which will look into matches that attract suspicion.

In an attempt to clamp down on corruption in the game, the ATP has banned players from accessing laptops at tournaments and has posted signs asking them to telephone a 24-hour hotline if they hear of anything untoward.

Wimbledon had stepped up security in players' dressing rooms this year on the advice of two former senior detectives who reported last month on the integrity of professional tennis.

Only the player and his or her coach will now be allowed in the dressing room, preventing access for entourages who might come under suspicion of gaining insider information to be used in gambling.

No players have been found guilty of match-fixing but five Italian men have been handed bans after being caught breaking tour rules by betting on matches. There was no suggestion that they had been trying to influence the outcome of matches.