Anquiletti Started his career in Serie D with Solbiatese during the 1964–65 season. In 1964 he played with Atalanta in Serie A, making his debut on 16 November 1964, at the age of 21, in a 1–0 away win over Cagliari; he remained at the club for two seasons. From 1966 to 1977 played for AC Milan, where he achieved notable success, forming an impressive defensive line-up during his 11 seasons with the club alongside Cudicini, Trapattoni, Rosato, and Schnellinger, which was nicknamed the "Maginot Line". He was notably part of their European Cup victory in 1969, also winning the 1967–68 Serie A title, two European Cup Winners' Cups (1967–68 and 1972–73), the 1969 Intercontinental Cup, and four Coppa Italia titles (1966–67, 1971–72, 1972–73, 1976–77). He notably scored two goals against Levski Sofia in the first leg of the first round of the victorious 1967–68 edition of the European Cup Winners' Cup. Overall, he made 418 appearances for Milan, and is the club's ninth all-time appearance holder; 278 of his appearances came in Serie A, 71 in the Coppa Italia, 63 in European Competitions, and 6 in other competitions. He ended his career with Monza, spending 2 more seasons in Serie B before retiring in 1979, at the age of 36.