I caught the last 40 minutes of this little gem on America's Major Leauge Baseball Network. I guess they got bored of playing reruns of old games in the middle of the night & started to play old movies about baseball as well. It's not the most popular movie, but it does include many examples of fine 1970s American sheet metal.

Bad News Bears: Break in Training 1977
http://www.imdb.com/title/tt0075718/?ref_=sr_2