The above video is a good introduction to how much sports games have changed over the years. However, it really only provides a sense of the looks and the sounds of the games without much else. Surprisingly Business Insider has a decent timeline on video games about sports.

1987: The expanded use of artificial intelligence and the rise of Electronic Arts

While AI was introduced in the years prior to 1987, it was until then that they became realistic.
Electronic Arts, the company now synonymous with sports games, released Earl Weaver Baseball. No baseball game released prior to EWB was anywhere close as beautifully graphically, and the baseball was actually realistic.
The game designers consulted the legendary manager Earl Weaver to help shape the game’s AI. As a result, EWB is still considered to be one of the best baseball games ever created.

Wikipedia also has good coverage of the history of sports games, perhaps the best I’ve seen so far. If you know of other sources that are good please leave it in the comments.

And above all else, let’s not forget that there is a living to be made by playing digital sports games.