Trivia

To get a more fluid camera movement in the boxing ring, cinematographer James Wong Howe filmed the fight while holding the camera and being pushed by an assistant wearing roller skates.

This film was originally supposed to have been a straight biography of three-time boxing champion Barney Ross. But after Ross publicly admitted that he had become a heroin addict from having received morphine to treat his wounds during WWII, the studio instead decided to turn the film into a fictionalized portrayal of Ross's boxing career. Ross sued and won a $60,000 settlement.

An extremely large number of the cast and crew on the film - writer Abraham Polonsky, actors John Garfield, Anne Revere, Lloyd Gough, Canada Lee, Art Smith, Shimen Ruskin, producer Bob Roberts and even, albeit to a lesser extent, cinematographer James Wong Howe - found themselves either blacklisted or grey-listed during the HUAC witch-hunts of the 1950s, while director Robert Rossen only avoided that fate by naming names.

A remarkable 12 members of the cast and crew had been or went on to become directors: actors William Conrad, Sid Melton, George Tyne and Joseph Pevney, writer Abraham Polonsky, cinematographer James Wong Howe, editor Robert Parrish, supervising editor Francis D. Lyon, montage director Gunther von Fritsch, art director Nathan Juran (aka Nathan Hertz), assistant director Robert Aldrich and script supervisor Don Weis. Additionally, set decorator Edward G. Boyle directed a film in the silent era.

The poem quoted by Peg Born (Lilli Palmer) is "The Tiger" by William Blake, an English poet and artist.