BOSTON – Zdeno Chara played well and delivered checks hours after Montreal police began an investigation of his hit two days earlier that left an opponent with a serious concussion and fractured vertebra.

Their captain’s performance wasn’t enough for the Boston Bruins to hold on to two leads Thursday night.

Brad Boyes scored at 3:44 of overtime and the Buffalo Sabres beat the Bruins, 4-3. What was Boyes thinking with an open net on his side at the right corner of the crease?

“I think ‘Don’t miss it,’ ” he said. “I think, get my whole body in the way if it bounces, tough ice out there at the end. If it bounces I have to make sure that whatever happens, it’s not going wide.”

For Chara, the challenge was to play his usual aggressive style. And he did that with an early hit on Jason Pominville that sparked chants of “Cha-ra! Cha-ra!” from the crowd.

“It’s something I very much appreciate,” Chara said. “I don’t see any reason to change my game or my style of play. I’m going to continue to play physical and play hard.”

Chara received a major penalty for interference and a game misconduct Tuesday night after slamming Max Pacioretty of the Canadiens into a padded stanchion supporting a glass partition.

“Obviously his state of mind is not at its best, which is normal,” Bruins Coach Claude Julien said about Chara. “You understand what’s going on. It’s not easy but, like I said, I thought he handled himself well tonight.”

The victory put the Sabres in a seventh-place tie with the New York Rangers in the Eastern Conference with 74 points and two games in hand. But the Rangers have two more wins.

“When you score in overtime this time of year it’s exciting,” Boyes said. “It’s about getting points now. It doesn’t matter who we play.”

His winning goal was set up by Nathan Gerbe, whose shot from 30 feet was stopped by goalie Tim Thomas, who seemed to lose sight of the puck after the save.

Gerbe retrieved it just to the right of Thomas and passed across the crease to an unguarded Boyes, who tapped in his 15th goal of the season.

“I just tried to get it on net as quick as possible and get the rebound,” Gerbe said. “I saw Thomas fumbled it a little bit.”

Thomas stopped 41 shots but couldn’t stop Boyes after Gerbe’s twisting shot.

“It was a knuckler,” Thomas said. “You can’t really control the rebound on that. You see strange shots when you give up (45) shots.”

The Bruins lost their third straight game after winning seven straight.

“Physically, we know they are good,” Gerbe said. “They are a top team and they have a lot of good players so we had to play them tough.”