Second of two star collaborations of actors Ryan O'Neal and Barbra Streisand. The first had been What's Up, Doc? (1972) about seven years earlier.
Diana Ross was the original intended star. According to a Barbra Streisand biography, Ross left the project after her brief affair with Ryan O'Neal turned sour.
Producer Jon Peters, who was Barbra Streisand's boyfriend at the time, has since said, "I talked Barbra into doing that ("The Main Event"). It was time for us to do another film and I felt a comedy was the best way to go."
Barbra Streisand's music on the soundtrack represented the music performer's first recordings into the genre of disco music.
Ryan O'Neal trained extensively for the role of a boxer in this film. O'Neal once said: "I had to box one hundred and fifty rounds just to prepare for this movie".