Isso é Arena (1989)
Por wikipedia
Arena is an American science fiction film directed by Peter Manoogian and starring Paul Satterfield and Claudia Christian. Set in 4038, Satterfield plays Steve Armstrong, the first human in 50 years to compete in the intergalactic boxing sport called simply "The Arena". The film was produced by Charles Band and features original music by Richard Band.
Lacking sufficient money for a ticket, Shorty attempts to raise the cash by gambling in an underground casino. The game is raided by the authorities and in the confusion, Shorty pockets the money. Caught in the act by crime boss Rogor (Marc Alaimo) and his enforcer Weezil (Armin Shimerman), Shorty is held for ransom. Steve promises to pay off the debt, so he reluctantly returns to Quinn and agrees to a contract. Remarkably he wins his first match with an alien named Sloth in an upset. He continues fighting, determined to prove that a human has what it takes to be champion, and soon becomes a top contender. Despite Rogor's multiple attempts to cheat, Steve ultimately wins the championship from Rogor's top fighter, an alien named Horn (Michael Deak).
Você pode assistir o filme completo no youtube (ATENÇÃO: NSFW - Violência).