Celebrities, they're just like us. They wear their baseball team loyalties on their sleeves ... and their hats. Major League Baseball is celebrating the baseball cap -- that humble, heartfelt fashion statement -- on Opening Day by encouraging fans of all stripes to sport their favorite team's hat at work or school and share a photo via the hashtag #CapsOn.
So, from superheroes to supermodels, rappers to rockers, and WWE wrestlers to leaders of the free world, we found a famous fan from each MLB team who already has his or her head in the game.
Superheroes
Ben Affleck
As the latest incarnation of the Caped Crusader in "Batman v Superman: Dawn of Justice," Affleck battled bad guys in Gotham -- just like he believes his beloved Boston Red Sox do when they visit Yankee Stadium.