Aguiar made his professional debut against John Cronk at World Vale Tudo Championship 4 on 16 March 1997, in the semifinals of the Vale Tudo 77kg tournament. He won the fight by a rear-naked choke, after almost ten minutes of continuous fighting, and advanced to the finals where he faced Antonio Santos. Aguiar won the tournament final by knockout, stopping Santos after just 49 seconds.[4]
Aguiar's last professional bout was against Matt Hughes at UFC 26: Ultimate Field of Dreams on 9 June 2000. Hughes won the fight by technical knockout, after the ringside doctor stopped the fight near the end of the first round.[6]