After leaving UCLA, Knox signed a movie contract with
Metro-Goldwyn-Mayer, but he never appeared in any pictures for the studio. Knox signed with the
Hamilton Tiger-Cats, but left the team after one month to once again pursue a film career. Knox signed with the
Calgary Stampeders on October 3, 1956, six days after quitting the Tiger-Cats. Selected in the third round of the
1957 NFL draft, Knox signed with the
Chicago Bears. He was suspended indefinitely by head coach (and owner)
George Halas in early October
1957 for violations which included his stepfather's public criticism of the team and missing two practices and a quarterback tutoring session without reason. Due to a bitter dispute with the Bears, Knox was not allowed by Halas to play for the Bears or play for any other NFL team. Instead, he signed with the
Toronto Argonauts midway through
1958 CFL season with a promise by Harvey Knox to the team that he would not interfere. His most notable performance came on October 25, 1958 when, playing the
Ottawa Rough Riders, he passed for 522 yards, then a team record and still second most in Argonaut history. After splitting up with his stepfather, Knox played only one more season of football before retiring, saying that football was a "game for animals". ==Post-sports==