Arena (1989)

Aliens have arena fights on an intergalactic space station to determine who is champion.  No human has fought or been champion in fifty years.  But young blond Steve Armstrong decides he wants to fight.  After beating up a fighter and training with a coach, he becomes a contender for the championship.

But the fighting world is full of villains and there are nefarious goings on which threaten Steve's match.  One of those things includes the night before the fight when Steve is seduced by the evil guys girlfriend.  Steve is an idiot. He shacks up with the girl and drinks a lot, not a good move, but especially bad since the wine has been poisoned.

It's not a movie you'll need a brain for, but if you like 80s space movies (which look ridiculous by today's standards) then it's kind of fun.