Manchester City and FIFA will be on the same side of an appeal case at the Court of Arbitration for Sport.
CAS says an appeal by Argentine club Velez Sarsfield to challenge the transfer of teenager Benjamin Garre will be heard on July 3.
Velez complained to FIFA last year that City broke rules preventing trafficking of minors by signing Garre after he turned 16.
The Premier League club said they could register Garre with the English Football Association and FIFA because he had an Italian passport.
FIFA respects European Union laws allowing free movement of 16- and 17-year-olds.
In September, FIFA said there was "no element justifying the opening of disciplinary proceedings against Manchester City."
City risk a ban on registering new players if Velez win the appeal.