max_readbafeldman Hard to be 100% sure. The games card is likely Google's crawl and transform of some data source, though they could be aggregating it by hand. MLB (dot) com sites + Wikipedia provide a ton of metadata...
max_readbafeldman Things like the Current Roster for example are likely pulled wholesale from Wikipedia. People generally underestimate how, simply by providing unchanging consistent HTML and API, Wikipedia tends to power a lot of the web.