In most cases, running the bases is not based on a true story. It's often a part of made-up scenarios in sports-themed entertainment or literature. Sometimes, elements might be inspired by real-life events, but as a whole, it's typically fictional.
Well, it depends. Sometimes the information on Wikipedia can be verified, but for this specific topic, it might require further digging and checking multiple references to determine if it's a true story.
I don't know for certain. It could be inspired by real events but might have taken some creative liberties. Maybe search for articles or comments from people involved in the making of the movie to get a clearer picture.