Already popular with the Ascoli fans because of his history as a former player for the club, Mazzone gained even more popularity by leading the team for twelve years, up to their historic first ever Serie A appearance. Successively, Mazzone coached several Serie A and Serie B teams, such as Fiorentina, achieving his personal best result in Serie A, a third-place finish during the 1976–77 Serie A season, also winning the Anglo-Italian League Cup in 1975. He subsequently coached Catanzaro, Bologna F.C. 1909, Lecce, Pescara, and Cagliari (1991–93), leading the team to its first appearance in a European competition since the times of Gigi Riva.