Boxer George Groves has allegedly been warned by police that gangsters have threatened to kill him during a live TV fight.
Groves, 23, pulled out of his British and Commonwealth super-middleweight televised title fight with Kenny Anderson on Friday night, citing a back injury.
His management have insisted the withdrawal was completely unrelated to the alleged threats.
Groves and his fiancé, Sophie, who live in Hounslow, West London, are not believe to be under police protection.
A source told the Sun newspaper: "George and Sophie were told by CID officers a threat had been made on his life and they should consider their safety. The intelligence said if he wasn't shot before the fight, it would happen in the ring."
A police spokesman has said: "We can confirm a threat to the welfare of a man was made to police in Hounslow."
In a statement Groves apologised for having to pull out of the Anderson fight but made no reference to the alleged threats.
"I am sorry to confirm I have had to pull out of my scheduled fight this Friday due to injury. I hope for a quick recovery but it just won't be in time for this week," he said.
"I truly apologise to everyone who has spent money and made plans around getting to the fight. I really don't want to compromise myself and under-perform because I am not 100 per cent fit."