Luton manager Mike Newell has revealed he has no written evidence to take to the Football Association to support his claims of a bung culture in the game.
Newell will meet FA officials to follow up his allegations that illegal payments are rife in transfer dealings.
"It's word of mouth," he admitted. "It's in my head, so I don't know if it's going to be any use at all."
Newell's comments during the past week have gained a mixed reception from other figures in the game.
And he has been told he needs hard evidence to back up his allegations.
On Saturday, football agent Dennis Roach said: "He has got to put enough evidence together before he comes out and speaks.
"He should take it to the FA to root these guys out, but if he hasn't got it he is in trouble.
Former Tottenham chairman Sir Alan Sugar also fears that Newell's allegations will come to nothing.
Sugar insists the practice of offering bungs is still "regular and orchestrated by agents."
But he added: "I don't wish to be sceptical but this is going to come to nothing and until such time as somebody goes to prison it isn't going to stop."
"It makes nice newspaper stories and there may be embarrassed faces and perhaps a few legal actions flying around.
"But at the end of the day, nobody will be going to jail."
Sugar has called for a tightening of rules and more transparency in agents dealings.
He said: "Unless some rules are put in place where an agent shows the authorities how he disperses the income he receives they're not going to get anywhere.
"They're going to have a hard job particularly if it's to do with foreign agents who don't fall under the jurisdiction of the British police or Inland Revenue."
Newell insists he is acting in good faith, though he appears to have backed down after telling the Daily Express on Friday that he would "present evidence of how a club director offered me a sweetener" to sell him a Luton player.
The former Everton and Blackburn striker said: "It will need somebody very strong to support me but nobody can question my integrity.
"Nobody at the FA can put me on a disrepute charge.
"The problem is if it's swept aside and there's nobody in the game to investigate.
"I will be very disappointed if I'm hung out to dry on this.
"If you feel passionate and believe in something, then you have to say it - and I've said it.
"If this causes me a problem in terms of my career, there's something seriously wrong in football."