A former Chelsea footballer claims the club paid him £50,000 to keep quiet about allegations of sexual abuse by a former chief scout.
Gary Johnson told the Mirror he had been abused as a youth player in the 1970s by Eddie Heath, who is now dead.
According to the Mirror, in 2015 Mr Johnson signed a confidentiality agreement and accepted £50,000 from the club, but they did not accept blame.
Chelsea said they had appointed a law firm to investigate a former employee.
The NSPCC children's charity said more than 860 people had called its dedicated football hotline, set up a week ago after several former players alleged past abuse by coaches.
The National Police Chiefs' Council said 55 amateur and professional clubs had been linked to police investigations in 17 force areas.
'Others out there'
Mr Johnson, 57, was a member of Chelsea's first team from 1978 to 1981.
He joined the club as an 11-year-old in 1970 and said he had been groomed from the age of 13 by Heath.
He said once the abuse had begun, Heath would attack him at "every opportunity", adding: "He would get me naked in bed, try more adventurous things."
He said: "During the course of this three to four years, he got me to perform in threesomes with other boys, so I know there are other victims out there - it is now up to them if they come forward."
Mr Johnson said he had kept the abuse a secret for decades, until the Jimmy Savile scandal had encouraged him to speak out.
He claimed the Professional Footballers' Association did not return his calls, but the PFA told the BBC it had spoken to Mr Johnson in May and August 2013, and had advised him to go to the police.
Mr Johnson told the Mirror that in 2014 he was advised by police - who have not commented on the claims - to "go back to Chelsea".
He went to a law firm who approached Chelsea for compensation.
"[Chelsea] basically said 'prove it'," said Mr Johnson. "It made me feel like they thought I was faking it."
The BBC understands that the confidentiality clause was lifted on Wednesday.
Mr Johnson said: "Chelsea are one of the biggest and richest clubs in the world.
"All their fans deserve to know the truth. I know they asked me to sign a gagging order. How many others are there out there?
"I hope and pray no clubs are allowed to cover this up - no-one should escape justice."
Mirror editor Lloyd Embley told BBC Radio 4's Today programme that Chelsea had been right to lift the confidentiality clause, but there were still questions as to why the money had been paid.
He said: "Premier League rules would seem to suggest that a club would need to come forward and say if they had evidence of child abuse."
Football Association chief executive Martin Glenn said: "We have clear rules in the game and if there's any evidence of a breach of those - and hushing up would be one - when it's our turn to apply the rules, we absolutely will, regardless of size of club."
In a statement, Chelsea said: "Chelsea Football Club has retained an external law firm to carry out an investigation concerning an individual employed by the club in the 1970s, who is now deceased.
"The club has also contacted the FA to ensure that all possible assistance is provided as part of their wider investigation."
On Thursday, a number of former Southampton players alleged that they were subjected to years of grooming and sexual abuse by a former club employee.
Southampton FC said they would co-operate fully with any police investigation.
A former Newcastle United player, David Eatock, also came forward on Thursday, to say he had been abused by coach George Ormond.
Sir John Hall, chairman of Newcastle United at that time, said he had not been made aware of any allegations or rumours of abuse when in charge.
'Way beyond football'
The sexual abuse charity Safeline said the abuse extended "way beyond" football, into other sports.
Neil Henderson, its chief executive, said the football revelations had prompted a 91-year-old man to call in.
He said: "He's lived with abuse for 80 years, and the courage of the footballers made him want to speak.
"We're getting people from schools, from scouts, from ice hockey, from different walks of life... we need to recognise that there are a lot more victims."
The FA is supporting the hotline set up by the NSPCC. It is available 24 hours a day on 0800 0232642.