A.C. Milan signed Boban in 1991 in a deal worth £8 million. Milan immediately loaned him to Bari, as they felt he needed time to settle in Italy without counting as one of the 3 non-Italian players the club was limited to at the time. Bari were relegated in this season, but Boban ably demonstrated his ability in the team and was recalled to Milan. He stayed in the club for nine seasons, and enjoyed great success with them, helping the team to the 1994 Champions League title and contributing to the 1995 campaign in which they ended as runners-up. Playing 251 games for Milan and scoring 30 goals, Boban won four Serie A titles, as well as three Italian Supercups. In the second leg of the 1994 UEFA Super Cup Final against Arsenal in Milan, he scored the opening goal in Milan's 2–0 aggregate victory. In August 2001, with his role at Milan diminished due to the signing of Rui Costa, he was loaned to La Liga side Celta Vigo where he played in only four league matches. Unhappy with his role as a substitute, he retired in October 2001 and finished his last season earlier than he intended.