Nearly three decades later, the “local artist” has a name. Up until the wife of the man who painted the Big Bat reached out to the Slugger Museum, John Yates’s identity was a mystery.

If you’re a baseball fan, there’s a good chance you’ve seen Little Big League. The 1994 film follows 12-year-old Billy Heywood, who wakes up one day and discovers he is now the owner and manager of ...