After a bruising bout with knockout artist Cassius Clay, aging heavyweight Mountain Rivera (Quinn) is told by a doctor his fighting career is over; he'll go blind if he gets in the ring again. With the help of kind-hearted social worker Grace (Harris), the boxer gets a break teaching kids at a summer camp, but the gig is sabotaged by Rivera's longtime manager Rennick (Gleason), who wants Mountain to don Indian feathers and play-act in a mob-owned wrestling match.
Nelson's heart-rending adaptation of an Emmy-winning teleplay by "Twilight Zone" maestro Rod Serling really lands in your gut. Quinn's performance as a sympathetically dim-witted palooka is the main attraction, but the cast is full of winners too: Rooney does solid work as Quinn's morale-boosting sidekick, and "East of Eden" star Harris is all heart as Grace. But Gleason scores big points as the grifter who offers Rivera a humiliating comeback to square a bet with some gangsters. This is one of Hollywood's best boxing films, right up there with "Body and Soul" and "Raging Bull."