Game and tryout scenes were filmed on location at Dodger Stadium in Los Angeles.
At the beginning, Bill is wearing a jacket that says 72nd Armored Division on the back. This indicated what unit he was assigned to when he served in the U.S. Army during the Korean war from 1951 to 1953.
In the scene where the owner is telling Ralph about the interview offer from Mike Douglas, you can see that the sound does not exactly match Bill Katt's lips when he repeats the name Mike Douglas. In fact, if you read his lips, it looks like he's saying Merv Griffin. Most likely, this means Merv Griffin was their first choice as the celebrity guest star but had to pull out, meaning the scene had to be relooped when Douglas was brought on.