Barcelona are locked in talks with Red Star Belgrade for defender Mihailo Milutinovic.
Milutinovic, 15, is rated Serbia's best young defensive talent to emerge since Manchester United centre-half Nemanja Vidic.
Barca want to add the youngster to their academy this summer, but Red Star are reluctant to sell.
Red Star youth coach Ivica Momcilovic said: "Mihailo plays for Red Star and Serbia youth, and it would not surprise me that Barcelona is interested. However, I cannot worry about whether or not the club is going to sell him."