Kovačić started training with the club's senior squad under manager, Vahid Halilhodžić, four months later, on 6 October 2010, but continued to appear for the club in academy league matches during October.
Gelandang muda mulai berlatih dengan skuat senior klub di bawah manajer Vahid Halilhodzic, empat bulan kemudian, pada tanggal 6 Oktober 2010, tetapi terus muncul untuk klub dalam pertandingan liga akademi selama bulan Oktober.