Brad Marchand was tripped in front of the Bruins bench and, as he skated by, James Neal drove his knee right through Marchand's head. Play stopped shortly thereafter and Bruins teammates converged on several Penguins, including Brooks Orpik. Earlier, Orpik knocked Louis Eriksson out of the game on his first shift.
Amidst the scrum, Shawn Thornton skated up to Orpik from behind, took him down and punched him right in the mouth. It looks like Orpik went slack immediately and Thornton, who was ejected, continued hitting him while he was down on the ice. Orpik was stretchered off the ice after a lengthy delay.
Update 9:04 p.m.:
[NESN]