Following evidence sent to the Football Association an investigation has been opened in relation to Gael Givet's transfer to Blackburn in 2009.
Givet moved to Rovers from Marseille in a £3.5million deal but the player has claimed he was forced to pay money to an unlicensed "agent" for helping to facilitate the switch.
Correspondence has now been sent to the FA, who will examine it closely before deciding how to proceed with the matter further.
FA rules strictly prohibit any third party being paid for a transfer unless a licensed agent.
"We will be looking into the material and the issues that may be raised by the content," confirmed an FA spokesman.