There are grave suspicions that money is being exchanged for tournament passes; that former players are being granted access to events and acting as insiders for gambling conglomerates; that whispers about injuries and arguments with girlfriends are being passed down the line, encouraging sudden surges of money on players who ought not to win but do. On the fourth anniversary of the first contest to alert the sport to the prospect of fixed matches, something is going to be done to clear up the mess.

The four stakeholders in professional tennis, led by the ATP, the governing body of the men’s game, meet in London this week intent on setting up the sport’s first “integrity unit”, the initial step towards driving conmen and potential fixers from their nests. Last month, the ATP set up a confidential hotline, insisting that “it is your [the players’] duty as a professional to report inappropriate or illegal activity involving corruption or doping”. The red phone has not rung yet. For the sport’s sake, it must.

At the ATP’s behest, those stakeholders will begin a review and risk assessment, working on plans required to police, prevent and deal with all forms of corruption in the sport, in cooperation with the British Horseracing Authority, which is advising on the latest gambling trends and how the ATP might cope with them.

Respected experts in this field have been approached and have agreed to meet representatives of the ATP, the Sony Ericsson WTA Tour (the women’s governing body), the ITF (the global governing body) and the grand-slam tournaments to set the wheels in motion.

It has been too long chugging into action. In October 2003, at a tournament in Lyons, Yevgeny Kafelnikov, of Russia, a former world No 1, French Open and Australian Open champion, was beaten in straight sets by Fernando Vicente, a Spaniard who had lost his previous 12 matches. Betting was suspended on the match after sums in the region of £80,000 were laid on Vicente to win. Kafelnikov, who had been carrying a foot injury, played in two more tournaments and then retired from the sport.

In between times, he staged a memorable press conference in Madrid. “I understand an article says Kafelnikov has been involved in match-fixing in tennis, it just completely tears me apart,” he said. “All I can tell you is tennis players have never been involved in the match-fixing. We are playing for our living. I’m completely hurting myself fixing any kind of matches. When I walked in yesterday morning, in the locker-room, all the players looked at me like I’m the worst enemy of all time.” Kafelnikov became a professional poker player.

Then, two months ago, came the voiding of all bets on the match between Nikolay Davydenko, of Russia, and Martin Vassallo Arguello, of Argentina, in Sopot, Poland. Davydenko, the world No 4, had begun the match at odds of 10-1 on, which lengthened to even money even after he won the first set. Huge sums were laid on Vassallo Arguello to win when he took the second set and Davydenko retired, injured, after three games of the final set.

Davydenko has been spoken to by the authorities, but an investigation that Etienne de Villiers, the ATP president, described as “incredibly complex” will require access to data such as where the money came from, where it went and the timing of the transactions. It could last several months. Both players denied any wrongdoing.

Subsequently, there has been a drip-drip of revelations from players who claim that they have been approached to throw matches and told those who approached them where to go.

Gilles Elseneer, of Belgium, said that he was offered €100,000 (about £69,000) to lose his first-round match at Wimbledon in 2005 and his compatriot, Dick Norman, said he had been asked to give details of players’ state of health, both physical and mental, in return for a few thousand euros. Arvind Parmar, the former Britain Davis Cup player, said that he “wanted to punch the guy” who asked him to throw a match at an ATP Challenger event a couple of years ago.

What the sport clearly needs to do is exercise more vigilant control over the people granted accreditation - and thus privileged access – to tournaments. Their numbers have swollen markedly over the past few years, in common with the increase in the size of players’ entourages. One of the fundamental elements of what the ATP has described as its “risk profile” will extend to evaluating tournament sites and hotels to see where access to players and others can be restricted.

It has become apparent that passes into tournaments are being purchased by those eager to get closer to the action, pore over practice sessions, sidle up to conversations between players, coaches and physios and pass on the information they glean to those who will gamble on its veracity. Tommy Haas, the German world No 11, said recently: “You hear stories and you wonder why we aren’t watching out for these guys at tournaments – there have been cases where it’s quite obvious.”

For De Villiers, this is a must-win situation and it was among the topics of a conversation he had with Roger Federer, the world No 1, last weekend. “The awareness of this has elevated through recent press coverage and I’m grateful for that,” De Villiers said. “It has flushed out a number of issues that players were reluctant to talk about before.

“The most positive thing is that it has galvanised all the bodies of tennis to do something – and do it now. It is no longer something we should do, it’s something we must do.

“Roger is completely convinced that it is not a problem among the top players, but he acknowledges that there can be potential vulnerability lower down the scale, where players may be less mature and can make a lot more money in these circumstances than a struggling tennis professional ever could simply by playing.

“What we need are better rules, better information and a stronger culture. And that means people claiming they have dossiers on the subject handing them over to the proper authorities.”

De Villiers is heartened by the reaction of Tennis Australia, which has taken a bold step by banning gambling on-site at next year’s Australian Open and beyond. Steve Wood, the Tennis Australia chief executive, said: “We have a zero tolerance for gambling and we’ll be providing additional security measures during the Open to monitor the environment.”

Elsewhere, there has been much finger-pointing. A French weekly newspaper, Le Journal du Dimanche, has claimed that several named Italian professionals had on-line betting accounts, an accusation that caused the Italian federation to summon its lawyers to protect its image against what it called a “media assault” against its players without proof.

The federation said that the diffusion of “generic accusations and unfounded insinuations” had gravely damaged the prestige of Italian tennis and came at a time when a serious investigation must be made into allegations of match-fixing. That investigation is about to begin in earnest.