About 10 years ago, went to the final game of the season between the Yankees and the Redsox at Fenway. The winner went to the playoffs. The loser's season was over. We walked through the old neighborhoods. Within 3 blocks of the stadium, there were riot police in helmets and vest on both sides of the street every 75 feet.
I asked why. The year before a Yankee female fan was killed by a Redsox mob after a NY game. They can get a little insane about their sports teams up in the NE.