You should read some of what they say about the Nationals on the Orioles Hangout. Not nice. I never knew so much hate existed between the 2 cities. I am sure this MASN dispute hasn't helped. Angelos is a terrible owner.
They had to cancel the annual Colts vs Redskins preseason games based on too many fights, the rivalry pre-dates MASN by a very long time, however Angelos is doing his best to keep it going.