Wimbledon chief executive Ian Ritchie said on Sunday there is no hard evidence of match-fixing in professional tennis and no one has produced fresh allegations.

Ritchie sought to play down stories in British newspapers, notably the Sunday Times, that several matches, including eight at Wimbledon, are under suspicion of being fixed by professional gambling syndicates after bookmakers noted unexpected spikes in betting patterns.

"Everything that was there [in the newspapers] was old stories. There was no new evidence and nobody's coming to us with new allegations," Ritchie told reporters on the eve of the tournament.

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Ritchie said Wimbledon has 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.

That report said 45 matches over the last five years had attracted unusual betting patterns and should come under review.

The review is continuing, Ritchie said, as part of the sport's drive to prevent corruption.

"There's a long way from peculiar betting patterns to match fixing...there's plenty of gossip but no real evidence," he said. "It's the elevation of tittle tattle to something that is given some significance that is wrong."

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.

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Ritchie said he is not complacent and had talked to the detectives Jeff Rees and Ben Gunn who compiled the report about locker room security, among other things. "It wasn't lax before," he said. "But we tightened it up."

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 have attracted suspicion.

The tennis bodies would soon agree on a common set of regulations and the appointment of a person to run the unit, Ritchie said. "What we are trying to do is prevent and deter...so we don't have a problem," he added.

The most high-profile case to arouse suspicion recently was a match between world number four Nikolay Davydenko of Russia [Images] and Argentine Martin Vassallo Arguello in Poland, where irregular betting patterns were noted.

Both players denied any wrong-doing.

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

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