BOSTON - Before Monday night's game at TD Garden, Buffalo Sabres coach Dan Bylsma warned the media that the Boston Bruins power play was essentially a sleeping giant that could awaken at any moment.
Entering the game, the Bruins had the 29th-ranked power play in the NHL at 7.9 percent (3-for-38). During the game, their alarm clock went off and they didn't hit "Snooze." Boston scored three power-play goals on eight attempts to beat the Sabres 4-0.
Video: BUF Recap: Sabres offense falters in 4-0 defeat
"It turns out to be the story of the game," Bylsma said. "… They were struggling on the power play, but they're a dangerous group. …And even though they weren't scoring, you could see it in their power play. We just gave them too many opportunities tonight to prove that they're a good group."
A three-goal second period littered with Sabres penalties helped lead the Bruins to victory. They scored twice in 7:07 of power-play time that period. The first came at the 5:44 mark when Brad Marchand put one in with Ryan O'Reilly in the box for tripping. The shot went off Lehner's mask, off his stick and in behind him. Matt Beleskey was parked in the crease for the screen and earned the secondary assist on the goal.
It was the second penalty O'Reilly committed during the game. O'Reilly has played 510 NHL games and only three other times in his career has he been called for four penalty minutes in a single contest. The last time was way back on Jan. 2, 2012. (He only has 76 career penalty minutes.)
"Looking at my two penalties and looking at where they were in the game and where they were on the ice, it's pointless," O'Reilly said. "I have to be more aware of my stick. Staying out of the box is huge. You can't do it - if you give their best players more time with the puck, as you can see, they put it in."
Buffalo then really got into penalty trouble when they were whistled for back-to-back four-minute infractions. They were able to kill off a four-minute double minor on Saturday to preserve a victory at Ottawa, but that wasn't in the cards against Boston.
First, Zemgus Girgensons was called for a high-sticking double minor after he clipped David Backes and drew blood 7:50 into the period.
Then with 2:34 left on Girgensons' penalty, Jake McCabe was called for tripping. On his way to the box, he was assessed an extra two minutes for unsportsmanlike conduct. That gave the Bruins a 5-on-3 advantage that they scored on with a goal from David Krejci with 9:48 remaining in the period.
"I didn't think I deserved one, but my reaction - getting an extra two hurt my team," McCabe said. "I've got something to learn from. It won't happen again."
The Sabres were able to kill off the remaining 3:05 of McCabe's penalty time.
But with 5:19 left in the second, a shot from Riley Nash beat Robin Lehner to make it 3-0. Boston is now 138-9-9 when leading after two periods since the start of the 2010-11 season. When they've led by three or more goals in a game over that time, the Bruins are now 120-1-2.
The Bruins held a 27-18 shot advantage after two periods, with 11 of those Boston shots coming on the power play.
"We've got to keep our cool no matter what's going on out there. You've got to stay composed, whether you're mad about it or not or you don't agree," Sabres captain Brian Gionta said. "We've got to keep our composure. That's what happens. The game gets running from you. You start reeling, you start getting frustrated and you get away from what you need to do to get back in the game."
A quick fight between Derek Grant and Beleskey provided some entertainment in the third after the Bruins spent a tad too much time in Lehner's crease. However that fight was the result of Grant interfering with Adam McQuaid, for which he was assessed a penalty.
David Pastrnak scored on the ensuing power play to make it 4-0 at 9:45 of the third.
Lehner made 38 saves in net for Buffalo. Tuukka Rask earned the shutout with 32 stops.
It's the second time Buffalo has been shut out this season.
"We need to start scoring more goals. We need to get more contribution from the back end and it's going to take a couple dirty ones," McCabe said. "We just need to keep sticking to the process and learn from our mistakes and look forward to the next couple games."
The Sabres have a scheduled day off on Tuesday and will return to work on Wednesday when they'll host the Senators at KeyBank Center. Faceoff is scheduled for 7:30 p.m. on MSG with the TOPS Gamenight pregame show starting at 7.