In the warehouse fire scene, all the firefighters except Dennis Quaid, Peter MacNeill and Jordan Bridges are real.
Dennis Quaid received 16 stitches just above his hairline after being injured in the stunt where he slides down the construction funnels during the warehouse fire. He had to remove his helmet as a story element. If not for that, he wouldn't have been injured.
On April 25, 2000, the New York Mets and Cincinnati Reds played a game wearing their 1969 uniforms to promote the film.
All of the World Series facts were true in this film. The Mets' Cleon Jones really did get hit on the shoe with a pitched ball. At first the umpire didn't award him first base, but when Mets manager Gil Hodges showed him the shoe polish on the ball, the umpire changed his call and awarded him first base. It became known as the "Shoe Polish Incident".
In 1997 Renny Harlin was going to direct the film with Sylvester Stallone playing the lead, but Stallone asked for too large a paycheck and eventually neither Stallone nor Harlin was involved in making the picture.