He started his youth career at the Paris-based clubs Paris Saint Germain and Red Star before going to FC Liège in the Belgian League.
He made his senior debut at FC Liège in the 1994–1995 season before playing for Lommel (KVSK United) and Club Brugge.
After leaving Inter, he had brief stints at Bolton, Derby County, Coventry City, Gent, Germinal Beerschot and KSV Temse.
He was part of the Senegal team that defeated reigning champions France in the opening fixture of the 2002 World Cup and made it to the quarter-finals.
However, before he made an appearance for Bolton, he collapsed prior to a match in October, and had to be fitted with a defibrillator due to an irregular heartbeat.
However, following a period of rest and passing a medical, Fadiga returned to the Bolton squad in early 2005 and played in five games.
At the start of the 2005–06 campaign, Fadiga was loaned to Derby County of the Football League Championship, making four appearances.