^ For the UFC Heavyweight Championship. Referee Herb Dean called a stop to the bout when he noticed a break in Sylvia's arm which appeared to Sylvia and the audience as an early stoppage; it was later revealed that Sylvia had indeed suffered multiple fractures to his right forearm.[1]
^ For the UFC Welterweight Championship. Hughes becomes the UFC Welterweight champion filling the vacant title. Hughes had previously lost the title to BJ Penn, but Penn had been stripped of the belt after signing with K-1.
Debut UFC fighters
The following fighters fought their first UFC fight in 2004: