Tommasi made his debut with Chievo in the 1993/94 season and quickly became recognised as a talented right-sided midfielder with clever distribution.
He became one of the most sought-after young players in Italy and was snapped up by Roma for the 1996/97 campaign.
There he won many admirers for his ability to win and keep possession - his tough tackling matching his accurate passing.
He made his international debut in a 2-2 draw with Spain in November 1998 but failed to hold down a regular spot.
A three-year absence from the national team followed, seeing him miss out on Euro 2000 altogether, before he was brought back into the fold in February 2001.