PITTSBURGH — The Boston Bruins left Pittsburgh with a loss and a whole lot of anger after one of their best players was injured on what they felt was a cheap shot.

Evgeni Malkin scored the go-ahead goal early in the third period, and the Pittsburgh Penguins remained unbeaten since the Olympic break by beating the Bruins 2-1 on Sunday.

Marc-Andre Fleury stopped 21 shots by the NHL’s lowest-scoring team to help the Penguins end Boston’s five-game road winning streak. Boston, which had won six of seven, is 1-1 during a season-long seven-game trip.

The Bruins played the final 5:37 without center Marc Savard, who received a concussion while being leveled by a blind-side hit by Matt Cooke. Savard released a shot from above the circles, only to be struck in the head from behind by Cooke’s raised left arm and shoulder. Cooke was not penalized.

Savard, one of Boston’s top players with 10 goals and 23 assists, remained behind at the team hotel Sunday night, along with a member of the team’s medical staff. The Bruins were unaware after the game of any medical problem other than the concussion, although they said Savard was unconscious briefly.

“It’s pretty obvious that was definitely a dirty hit,” said Bruins Coach Claude Julien, who said Cooke should be suspended. “That’s probably the classic blind-side hit to the head.”

NHL general managers are considering a rule change for next season that would ban such hits, but the Bruins still believe Cooke’s hit crossed the line. Cooke defended himself, saying he was only finishing his check.

“At some point, there’s got to be a clear indication from the league (what’s legal and what’s not) because we’ve seen this so many times now,” Penguins captain Sidney Crosby said.

“You don’t like to see anyone, your own teammate or an opposing player, lay on the ice like that.”

The Penguins are 4-0 since Crosby scored the winning goal for Canada against the United States in the Olympic gold-medal game.

Boston took a 1-0 lead when Blake Wheeler scored on a power play early in the second period.

Pascal Dupuis tied it at 8:57 of the second. Dupuis took Crosby’s giveback pass along the goal line and was twice denied by Tim Thomas before finally shoving the puck — and the goalie — into the net.

“I just tried to jam it in there,” said Dupuis. “He had his pad on it and I just pushed his pad a little bit behind the goal line and took a couple of whacks on it. I saw (Mike Rupp) on the other side pushing the other leg, so I knew the goalie was going to go into the net.”

Thomas said there was nothing he could do to prevent the goal.

“It’s frustrating as a goalie because, to be realistic, they let that go every time and it’s impossible to hold your leg against the post,” Thomas said. “A guy’s pushing you into the net; it’s ice, you slide, there’s no way to hold yourself.”