After an impressive spell with Pisa, Fortunato returned to the "Grifoni", where he made his Serie A debut on 6 September 1992, in a 1–1 away draw against Fiorentina. He teamed up with right-back Christian Panucci, another promising Italian full-back, and together they formed a formidable defensive young partnership. In his first year in the Italian top flight, Fortunato made 33 appearances and scored 3 goals, including the equaliser in a 2–2 home draw against eventual champions Milan, which helped Genoa avoid relegation.