Requiem for a Heavyweight (1962)

Mountain Rivera is at the end of his boxing career after a knockout by Cassius Clay in the seventh round. His left eye is one punch from permanent trauma, his ears turned to cauliflower, his speech slurred from "being hit a million times," and he slings punches anytime he hears a bell, but his trainer and 'cutman' Army, and Miss Miller, a manipulative social worker, support his illusion that he could be a movie usher, a camp counselor, or a romantic partner for Miller. But his manager Maish Rennick, knowing the truth, can't admit that he's bet everything he had that Rivera wouldn't go four rounds against Clay. Maish will pay with his life when the goon squad comes to collect if he can't persuade Rivera to abandon his pride ("I fought 111 fights and never took a dive") and agree to a wrestling contract of which he's ashamed. When Maish blurts out his secret, Rivera realizes that walking out on the deal is not an option. To save the neck of the man who's betrayed him, he embraces the humiliating role of wrestling as "Big Chief Mountain Rivera," and the illusion of camaraderie among the three men is gone forever.