Now another illustrious name can be added to the list, Barcelona.
The 17-year-old is already a senior Croatian international and is likely to feature at next summer's World Cup where his price tag and list of suitors could only increase.
Currently playing for Dinamo Zagreb, the 'new Luka Modric' could be headed to the rivals of the real one.
Spanish newspaper Mundo Deportivo writes:
"Dinamo Zagreb president (Zdravko Mamic) said that we have a written offer from Barcelona for Halilovic including variables of 15 million euros."
They also write that Tottenham have made a £13 million offer, while Bayern and Inter Milan have also initiated talks.
Halilovic has made five Europa League appearances this season and also featured in Champions League qualifiers. He also played in the FIFA under-17 World Cup in October.
Is he worth £15 million? Check him out in action below...