Retrosheet Play-by-Play Data
Event files provided for each game since 1913
Data for each play (similar to what you might find on a baseball scoresheet).
Event files are provided as zipped collections by season. One file covers a teams season of games.
Example line:
play,3,1,bichb001,01,CX,D8/L89XD+.1-3
Translation:
In the 3rd inning, with the visiting team (Blue Jays) at bat, Bo Bichette hit a double to center field. The ball was lined to center and involved both the center and right fielders. Due to a misplay or error, the batter advanced beyond the expected base. Additionally, a runner who was on first base advanced to third base on the play. `