The BBC and BuzzFeed News report that they have uncovered evidence of "widespread suspected match-fixing at the top level of world tennis," including at Grand Slam events including the Wimbledon championships.
In the past 10 years, 16 players who have ranked in the top 50 have been repeatedly flagged to the Tennis Integrity Unit over suspicions they have thrown matches, said the BBC.
All of the players, including winners of Grand Slam titles, were allowed to continue competing.
The documents passed to the BBC and Buzzfeed include the findings of an investigation set up in 2007 by the Association of Tennis Professionals to look into suspicious betting activity after a game involving Nikolay Davydenko and Martin Vassallo Arguello.
Both players were cleared of breaking any rules, but the investigation developed into a wider enquiry about possible match fixing.
ATP president Chris Kermode told the BBC he is aware there is match-fixing within tennis but says it is at an "incredibly small level”.
The BBC said that the documents it obtained - received from “a group of whistleblowers within tennis" - show the enquiry found betting syndicates in Russia, northern Italy and Sicily making hundreds of thousands of pounds betting on matches investigators thought to be fixed, including three at Wimbledon.
The corporation contacted Mark Phillips, one of the betting investigators in the 2007 enquiry, who told the BBC that they discovered repeated suspicious betting activity about a clear group.
"There was a core of about 10 players who we believed were the most common perpetrators that were at the root of the problem," he said.
"The evidence was really strong," he added. "There appeared to be a really good chance to nip it in the bud and get a strong deterrent out there to root out the main bad apples."
