Kovačić made his Inter Milan debut three days later on 3 February, coming on as a half-time substitute in a Serie A match against Siena. On 14 February, Kovačić made his European debut before the home crowd at San Siro in UEFA Europa League match against CFR Cluj. He provided the winning assist for Rodrigo Palacio, who made it 2–0 for Inter, impressing the crowd with his performance, and was given standing ovations while being substituted off in the 89th minute. He also played full 90 minutes in the 3–0 away win against CFR Cluj as Inter proceeded to the next round of the 2012–13 UEFA Europa League.