Years later, Sylvester Stallone explained why he agreed to appear in this movie, saying, "(Producer) Menahem Golan kept offering me more and more money, until I finally thought, 'What the hell - no one will see it!'"
Sylvester Stallone was reportedly unhappy with the final film. In an interview with the Ain't It Cool News website, he said that if he had directed the film he would have made it with a darker tone - changing the setting to an urban environment, using scored music instead of rock songs, and making the Las Vegas finale more ominous.
John Wetton, lead singer of the rock group Asia, sang "Winner Takes It All" for the movie, but after performing the song, it was felt that his voice wasn't "mean" enough, so the song was offered to Sammy Hagar, whose version ended up being the one on the soundtrack.
Rick Zumwalt, who played Bull Hurley, was actually the studio's third choice for Stallone's rival. They originally wanted Arm Wrestling Champion Cleve Dean, but he was too massive as compared to Stallone that it wouldn't have looked believable, so they went with Professional Wrestler Ox Baker. When Baker didn't pan out, the role went to Zumwalt.
In one of the final matches Stallone goes up against Mad Dog Maddison, played by Randy Rainey. Interestingly, the next year in 1988 they would come up against each other again in Rambo III. Rainey played the Russian Special Forces soldier who perished in the final scenes with a snapped neck and then blown to bits.