Retrosheet is a project which reconstructs historical baseball games from old newspaper accounts, scorescards purchased at estate sales, and other means. They actually have an ASCII scorecard format:

https://www.retrosheet.org/eventfile.htm

Originally to parse these out people used MS-DOS utilities written by the guy who made the Diamond Mind Baseball game. There's a more modern set of utilities called Chadwick now so you don't have to use DOS.