Fulham are facing the possibility that they may be banned for a second time this year from making any international transfers, over issues arising from unpaid debts on previous deals.
The first ban was implemented in January by Fifa, football's world governing body, in a move that Fulham chose to keep secret as they took rapid action to see it lifted.
The ban arose because of an outstanding debt of £3.2m owed to the French First Division club, Lyon, from the £11.5m transfer of Steve Marlet in July of 2001.
Fulham could find themselves facing a second - potentially more disruptive - ban over an alleged debt owed to Metz arising from Fulham's sale of Louis Saha to Manchester United earlier this year.
Metz, for whom Saha played between 1997 and 2000, claim they are due a sell-on fee from that deal, worth 15 per cent of the profit Fulham made when selling the centre-forward Saha for £12.8m to United.
Metz say they are still owed £1.3m and claim they have failed to receive any response from Fulham to their inquiries made while chasing the debt.
Metz's president, Charles Molinari, has decided to complain to Fifa about the matter. "We know it might take months but we will be patient," a club spokesman said.
A Fulham spokeswoman said the club had no comment to make on the matter. "It is in the hands of our legal experts."
If Metz do not receive payment, it is likely that Fifa will refer the case to the Court of Arbitration for Sport, the Switzerland-based independent body that rules on sporting disputes.
The Fulham-Lyon case over Marlet was also referred to the CAS and it was the CAS that demanded Fulham pay Lyon. Failure to do so led to the transfer ban in January. Fulham denied yesterday that January's ban "prohibited us from signing any players" but this appears to be semantics rather than fact.
Faced with the ban, Fulham acted so rapidly in settling their debt to Lyon that the ban did not disrupt any planned signings. Yet the ban had been served and was in place on 21 January.
"This ban comes into effect today," Fifa confirmed in a letter dated 21 January to Mark Palios, then the chief executive of the Football Association. It was Palios's job to enforce the ban in England.
A Fifa spokesman told The Independent yesterday: "I can confirm that Fulham was placed under an international transfer ban on 21 January, 2004, a ban that was in place until confirmation had been received by Fifa that Olympique Lyonnais had received the monies owed to them for the transfer of Steve Marlet."
Faced with the ban, Fulham made immediate payment to Lyon, meaning they were free to sign the USA international Brian McBride within days.
According to Chris Synnott, a solicitor who acted for Lyon in the Marlet case and who now works for the West End firm, the Simkins Partnership, said: "Fifa envisages the CAS playing an increasingly active role in football-related disputes as part of Fifa's wish that disputes are, wherever possible, resolved within the football family.
"To this end, clubs should be aware that the threat of transfer bans and/or points deductions is a very real one in the event of non-compliance with a CAS decision."