The ATP, the governing body of the men's tour, promised to look into all allegations of match-fixing by players in order to protect the sport's integrity.

Speaking in the wake of a newspaper report claiming that players had deliberately thrown matches for financial gain, ATP spokesman Nicola Arzani said that the organisation would do everything to keep the sport clean.

"Anything suspicious will be looked into," Arzani said in the Spanish capital as the Madrid Masters began.

"The ATP is taking everything seriously. The integrity of tennis is paramount."

The ATP are aware that gambling scandals have battered the image of other sports, including cricket, and a system of penalties has already been put in place.

Any player found guilty of match-fixing would be banned for three years and fined $100,000, Arzani said.

"Gambling has affected other sports," he said. "There are rules in place in tennis. A three-year ban would effectively mean the end of someone's career and the feeling of the players is that they would never forgive anyone who cheats."

BETTING RECORDS

Arzani said that the ATP had entered into a letter of understanding with Betfair, the internet betting company at the centre of claims, to look into the allegations.

The ATP first learned of concerns about betting more than three months ago which prompted it to sign the agreement with Betfair.

The agreement is similar to one the betting exchange has with the Jockey Club. Under the agreement, the ATP can ask to see betting patterns, which will be supplied.

The ATP can then make a further request for named betting details, but these will only be supplied if Betfair are "100 per cent satisfied" that there is a case to answer.

A report in the Sunday Telegraph alleged that "fixes" came to light when bookmakers discovered that some matches were attracting a far greater betting turnover than they should have.

Last week bookmakers suspended betting on the match between Yevgeny Kafelnikov, of Russia, and Fernando Vicente, of Spain, in Lyon six hours before it was due to start after receiving bets from "marked accounts".

Although there is no suggestion that either player was involved in wrongdoing, according to the Racing Post a huge worldwide gamble was made on Vicente, who won 6-2, 6-3.

The Spaniard had not previously won a match since June, losing 11 first round matches until Lyon. His odds were reduced from 7-2 to long odds-on favourite on one of the Internet betting exchanges.

Fixed odds bookmakers suspended betting six hours before the match was due to start.

One firm, Skybet, has decided to stop accepting bets on the early rounds of minor events.