The talented 30-year-old Arizona Diamondbacks pitcher is perhaps best known to baseball fans for taking a ball to the head in the summer of 2012 while pitching for the Oakland Athletics, but he’s really made a name for himself on Twitter — before and after the injury. McCarthy dabbles in baseball theory (he’s one of the game’s most outspoken proponents of sabermetrics), social activism and playful banter with his wife (@Mrs_McCarthy32). If something important has happened and you’re looking for an athlete’s opinion, he should be your first stop. —Eric Dodds