The FA is looking into allegations made by Blackburn defender Gael Givet, who has claimed that an unlicensed middleman demanded £50,000 for his role in the Frenchman's move to Ewood Park.
Givet, 29, first arrived at Rovers in January 2009, before making his loan move permanent four months later in a £3.5 million move from Marseille.
The former Monaco centre back has now alleged that Manchester tailor Phil Black, who is not a registered agent with the FA, contacted him about setting up the move to Blackburn.
As part of an investigation by UK newspaper The Sun, Givet claims Black picked him up from an airport and took him to meet then-Rovers boss Sam Allardyce, before then asking for money for his 'role' in the transfer.
When Givet's agent rejected the advances Black allegedly turned to the defender himself, with Givet claiming he was "shocked" when the tailor demanded £5,000. Givet said: "It felt wrong. I was very uncomfortable."
He added: "Black kept on asking me for money. He kept saying he should have been paid and had received nothing. He told me he needed money because he couldn't pay his mortgage, he needed money to keep the bank off his back."
The Frenchman claims he handed over £5,000 in an envelope before transferring £15,000 into Black's bank account and topping it up with a cheque for £30,000.
Black, who the paper says later returned £15,000, insists the total was less than Givet claims and that he was entitled to some money.
"From what he's getting - 65 grand a week - I don't think £5,000 is a big present, do you?" Black told The Sun . "It's not been a case of that [acting as an unlicensed agent]. I just did it as a favour. I have been involved in football all my life - I have just helped people out."
An FA spokesman said: "We will be looking into the material and the issues that may be raised by the content provided by The Sun."