The bleachers turned into a battleground Sunday when a brawl broke out during the Chicago Cubs and White Sox game at Guaranteed Rate Park.

Chicagoans are always ready to toss insults at each other as North and Southsiders hit the field for the famed crosstown classic, but it doesn’t always turn to fisticuffs. Still, on Sunday, the rivalry boiled over in the bleachers for the final game of this season’s interleague matchup.

Though there is plenty of video, it isn’t completely clear why the shoving began, but a least one video shows a fan bounding up the bleachers and smacking into another fan, knocking his beer to the floor. That is when the first fan was pushed over, and the shoving matches began.

From there, the shoving intensified, and the fists began flying amid a shower of numerous cups of beer that were thrown down into the middle of the melee.

As expected, in this day of ubiquitous smartphones, there is plenty of video:

It isn’t sure if anyone came out on top in the bleacher brawl, but the Sox dominated the Cubs five games to one during this year’s Crosstown Classic. And on Sunday, they really wiped out the Cubbies, beating them 13 to 1.

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