Thornton suffered the head injury during a first-period fight with John Scott in last night’s loss to the Sabres.

Thornton was wobbly after the fight, and did not return to the ices. He served a five-minute major, but went to the dressing room from the penalty box.

The Bruins also recalled right wing Jamie Tardif from Providence on an emergency basis.

“Unfortunately, there’s always a risk with that job,” coach Claude Julien said of Thornton. “He took on a pretty big man as we all know, 6-8 and maybe around 280 pounds. He handled himself as best as he could. But those things are going to happen.

“At the end of the day, he was still willing to do it for his team. Not only do we lose a guy that does it well, but he’s a good teammate and he’s great in the dressing room. Hopefully we get him back soon.”