 Clementi began his professional career in 1999 and amassed a 13–6 record before making his Ultimate Fighting Championship (UFC) debut at "UFC 41", where he lost by submission to Yves Edwards.Clementi continued to fight in smaller promotions before appearing as a contestant on "The Ultimate Fighter 4" reality show, which focused on promising fighters that had not succeeded in their UFC careers.Though the namesake of "Team No Love", Clementi lost his preliminary bout against Shonie Carter by unanimous decision.