Inter Milan chief Piero Ausilio is delighted with Mateo Kovacic's new deal.
The midfielder has signed to 2019.
"His contract renewal is critical, because he's one of the best European talents," Ausilio told Inter Channel.
"The fact that he has decided to commit to us for so long means that he believes in our project, and in the future of [Coach Roberto] Mancini and [President Erick] Thohir's Inter.
"I see it as a vindication of the work we're doing, Inter is seen as a serious club.
"Mateo is one of the foundations on which we want to build Inter, but we'll also do it with other players. We're choosing talented kids, young people who can mature here.
"Now our aim is to monitor others, to continue the great scouting work we're doing, not least because we have some economic restrictions."