Manchester United target John Mikel Obi has been ordered by Fifa to return to his Norwegian club Lyn Oslo.
Obi claims he was 'forced' to sign for United
The 18-year-old Nigerian failed to resume duties with his club after playing for his under-20 national team at the Fifa World Youth Championship.
Fifa's dispute resolution chamber has now told the player to return.
Fifa's decision may have implications over his move as it proves he was a Lyn Oslo player when a deal was struck - something which had been in question.
Obi has said he is not keen on moving to Old Trafford - while Chelsea have also expressed an interest.
He said in a television interview he was bullied into the move by officials from United and Lyn - something claim both clubs have denied.
When the row erupted in April, Mikel was spirited out of Norway and has not returned, despite appearing for his country in the World Youth Championships this summer.
Reacting to Fifa's decision, John Ola Shittu, the agent who claims to have the authority to represent Obi, told BBC Sport that the player will be appealing against the decision.
"This is a questionable decision and we want to know how it was reached," said Shittu, who was named in the complaint filed by Lyn and Manchester United of playing a role in unsettling the player.
"If we have to we will go all the way with this. Mikel has nothing more to say on the matter for the time being," Shittu claimed.
According to article 60 of the Fifa Statutes, this decision may be appealed before the Court of Arbitration for Sport (CAS) in Lausanne, Switzerland.