Snooker world number one John Higgins has reportedly agreed to take a £261,000 bribe to lose frames in four separate matches later this year.
The News of the World alleges it has video images of Higgins and his manager Pat Mooney at a meeting in Ukraine.
There is no suggestion Higgins has ever thrown a frame or fixed a match and neither he nor Mr Mooney has responded to the publication of the story.
Mr Mooney is quoted in the paper saying he feared for his safety at the time.
He is reported to have told the News of the World: “You have no idea what the circumstances were in Kiev, that’s why I have no comment.
“But we were genuinely in fear for our safety.”
The paper says three-time world champion Higgins has refused to comment.
It alleges that the conversation took place on Friday and Higgins inquired about the best ways to conceal the money to be received.
In a published transcript, Higgins, 34, from Wishaw, North Lanarkshire, says it would be easy to affect the outcome of a frame so syndicates could place bets.
Mr Mooney is a board member of the World Professional Billiards and Snooker Association, whose commercial arm is World Snooker.
World Snooker chairman Barry Hearn is quoted as saying: “If true, these allegations are a very serious matter indeed and a massive massive blow to the integrity of the sport”. He said an inquiry would be launched.
The World Snooker Championship final begins in Sheffield later.