The agent of Nikola Vlasic is unsure of his future with Torino.
The West Ham midfielder has spent this season on-loan with Toro.
Tonci Martic admits Vlasic's future is dependent on the opinion of West Ham management.
He told Sportitalia: "This year he did very well but I think he still has a lot of room for improvement.
"Nikola is happy in Turin, I hope he grows together with the team and coach (Ivan) Juric is very important for his career.
"It's hard to say whether he will stay or not. It depends on the club and West Ham: everything is still open."