After having started his journey in football with Italsider in Bagnoli, he was noticed and bought by Napoli, with whom he won the Under-17 championship in 1987, before being promoted to the first team. He signed for Parma in the summer of 1995. In his first seven seasons with the Gialloblù, he won two Coppa Italia titles, one Supercoppa and one UEFA Cup, forming one of the strongest defences of all time alongside Thuram and Buffon.

In 2006, he captained Italy to a historic World Cup win. His performances at the tournament in Germany saw him named as the FIFA World Player and won him a Ballon d’Or, becoming just the fifth Italian to win the prestigious personal award.