Penguins defenseman Brooks Orpik left the TD Garden ice on a stretcher following an altercation in the Penguins' Saturday night contest against the Boston Bruins.

Orpik was taken to Massachusetts General Hospital, where he was alert and conscious. He rejoined the team and traveled back to Pittsburgh following the game.

"I think (Orpik) was (unconscious) on the ice for a period of time," head coach Dan Bylsma said. "I think that means he has a concussion, for sure.

"He went through a battery of tests at the hospital for various things. He will be returning home with us."

Orpik was in the middle of a scrum of players when Boston’s Shawn Thornton grabbed him from behind and pulled him to the ice. Thornton then delivered two punches to Orpik's head.

Orpik lay motionless on the ice and was attended to by athletic trainers and doctors. After a few minutes he was placed on a stretcher and taken off the ice. Thornton was given a 10-minute match penalty and removed from the game.

"Listen, I feel awful. It wasn’t my intention," Thornton told the Bruins official website. "I know 'Broosky,' I’ve gotten to know him over the last seven years here, I skate with him in the summer, through the lockout. I’ve texted him a couple of times. I definitely feel awful. It was not what I wanted to see or what anyone wanted to see.

"Obviously, I made a mistake. I’m aware of it. I’ve been told that I’ll be having a hearing (with the NHL) and it’s hard for me to say much more other than that was not my intention. I feel awful and felt sick all game, so."

Orpik delivered a big hit on Boston’s Loui Eriksson, who suffered a concussion, in the game’s opening minute. Thornton challenged Orpik to a fight a few minutes later, but Orpik declined. Thornton received a two-minute penalty for roughing in that sequence.

"The hit from Orpik is a good hard hit; Eriksson touches the puck," Bylsma said. "The puck takes a strange bounce coming around the wall, but he does touch the puck. It's a good hit."