Two of my favorite players in MLB are now Red Sox. Any of your favorite players with a rival team now?
John Smoltz and Rocco Baldelli. This sucks man, now I have to root against them.
Oh you will soon, Believes, oh yes, you will, lol. They are for sure rivals as long as they stay decently competitive. Wouldn't call it a rivalry though. I'm sure it has the potential to become one, although not storied like the Red Sox/Yankees.
When I said root against them I didn't mean them personally. I will be rooting against the team of course. I'd never root against them personally, especially Rocco, that would be pretty foul. As posted in my question I never said "former" favorite players.