The coming weekend of May 16-18 presents a new schedule wrinkle for Major League Baseball and it's been branded "Rivalry Weekend."  To be sure, it's a bit of a contrivance, and Rivalry Weekend notably does not include the sport's most time-honored blood feuds like Yankees-Red Sox,

The New York Mets will play a Subway Series against the New York Yankees this weekend, here's how to watch every game for free!

However, there’s a different reason for the designated rivalry here, and it only has a little bit to do with geography. Specifically, how MLB’s divisions used to be aligned decades ago. In the 1980s,