Tassotti became a central figure in the Milan squad of the late 1980s and early 1990s under Arrigo Sacchi, and subsequently Fabio Capello, usually wearing the number 2 shirt. Tassotti was a key component of a strong defence alongside Paolo Maldini, Franco Baresi and Alessandro Costacurta, playing predominantly as a right-back and on occasion as a centre-back, in front of goalkeepers Giovanni Galli, and subsequently Sebastiano Rossi. The back four of the Milan side of this period is regarded as one of the greatest of all-time. Under Sacchi, Tassotti was named vice-captain after Baresi, and he won the 1987–88 Serie A title, followed by the Supercoppa Italiana, and consecutive European Cup titles, in 1989, and 1990. In addition, Tassotti won two Intercontinental Cups (1989, 1990) and two UEFA Super Cups (1989, 1990), also reaching the 1989–90 Coppa Italia final. During the 1987–88 season, Tassotti helped Milan to only concede 14 goals in Serie A, finishing the year with the best defence.