Fifa have refused to sanction Fulham's move to sign Rangers striker Daniel Cousin.
The Gabon international striker was hoping to complete his protracted £3million move from Ibrox to Craven Cottage.
Both clubs had been hopeful of the move going ahead before Thursday's transfer deadline, even though Fifa's regulations forbid a player from appearing for more than two clubs in one season.
Cousin had played 20 minutes as a substitute for French club Lens before his summer switch to Rangers but football's governing body are sticking rigidly to the rules and have cancelled the deal.
A Fulham spokesperson confirmed: "Daniel has had to return to Rangers because Fifa won't change their policy on a player playing for more than two clubs in one season.
"Unfortunately, that means we will not be able to welcome Daniel Cousin to Fulham."