They Never Come Back - Fred C. Newmeyer

Prizefighter Jimmy Nolan, facing an opportunity to get a championship fight, is knocked out when he sustains what is apparently a permanent injury to his arm. From there, Nolan's path leads downhill. He is drawn into a romance with a nightclub entertainer, then is framed on a theft charge by a jealous suitor. After his prison term, Nolan makes a spectacular comeback in a fight which proves his courage and integrity, while disproving the fallacy about the old sports adage that "they never come back."