The Cowboys didn't show much fight on Sunday night -- but their fans sure as hell did ... getting into wild brawls at a playoff watch party at AT&T Stadium.
One of the bigger scraps at the event happened following Dallas' lifeless 19-12 loss to the 49ers ... when a fan in a CeeDee Lamb jersey slammed a man in Ezekiel Elliott gear straight to the ground.
Fists immediately began flying between the two ... with both guys landing huge blows on each other's faces.