Fling in the Ring (1955)

"A knockout of a knockabout comedy!"

The stooges are the trainers of "Chopper", a beefy boxer, and they bet their bankroll on Chopper to win his next fight. When "Big Mike", their boss, tells them to have Chopper lose or they'll lose their lives, the boys try to soften up Chopper so he'll lose. The fight gets canceled and the stooges have to contend with an angry Big Mike and his goons.