Roy Keane would be able to play in Europe this season if he chose to join Bolton Wanderers, although he could not do so for Real Madrid.
The 34-year-old played for Manchester United in the Champions League qualifier against Debrecen but played no part in the group stages.
Under new regulations, the Corkman would be eligible to play in the last 32 of the UEFA Cup, should The Trotters progress by taking a point from tonight's game with Sevilla.
A FIFA spokesman said: "The UEFA Cup is regarded as a separate competition at this stage."
Meanwhile, according to The Sun newspaper, Keane is set to sign for Celtic in a sensational move in the next 48 hours.
