During his long and illustrious coaching career, Bagnoli is best remembered for being the manager which led an underdog Verona side to its first (and so far the only) Serie A title during the 1984–85 season; Bagnoli was in charge of a team which featured several promising players who had been unable to fulfil their potential until then, such as Pietro Fanna, Roberto Tricella, and Antonio Di Gennaro, but who later played a key role in the club's league title success as they matured. Bagnoli was the club's head coach from 1981 until 1990; in addition to winning the league title in 1985, during his time with the club, he helped Verona obtain promotion to Serie A in his first season, winning the 1981–82 Serie B title, and the following season, he led Verona to a fourth-place finish in the league and the Coppa Italia final, qualifying for the UEFA Cup. He left the club after they were relegated to Serie B once again at the end of the 1989–90 season.