The song "The Greatest Love of All", first introduced on the soundtrack of this movie by George Benson, went on to become an international smash hit for Whitney Houston in 1986.

Final project by Director Tom Gries, who died over four months before the movie's May 1977 release.

According to Ernest Borgnine in his biography, there was a strong relationship which rose between him and Cassius Clay during the shooting. Muhammad Ali cried when he saw Borgnine's character weep during one scene.

Part of a cycle of ring fighter movies, mostly boxing, some wrestling, initiated by the box-office and critical success of the Academy Award Best Picture winning boxing movie "Rocky (1976)." The films include "Rocky II (1979),""Rocky III (1982)," "Rocky IV (1985)," "Tough Enough (1983)," "Title Shot (1979)," "Raging Bull (1980)," "The Champ (1979)," "Matilda (1978)," "The Main Event (1979)," "The Prize Fighter (1979)," "The Greatest (1977)," "Body and Soul (1981)," "Paradise Alley (1978)," "...All the Marbles (1981)," "The One and Only (1978)," "Every Which Way but Loose (1978)," and "Any Which Way You Can (1980)."

Paul Winfield who plays the draft lawyer, went on to play Don King, Muhammad Ali's promotion manager in "Tyson (1995)."

Sharon Stone met Muhammad Ali when she was 17. She was in the Miss Pennsylvania pageant and Ali was in Hershey, Pennsylvania, when Stone was there and she met him. And then Ali called her father and offered her a part in his film that he was making (The Greatest). The late boxing champ predicted movie stardom while her father was skeptical. Sharon Stone's father said, ''She is not going to be in film.'' Ali told her father, ''You may think that she is not, but she is. You cannot hide that girl under a bushel basket. Her light is too bright.".