BOSTON -- Tuukka Rask made 32 saves, and the Boston Bruins scored three goals in the second period of a 4-0 win against the Buffalo Sabres at TD Garden on Monday.
Rask has won four of five consecutive starts since returning from an undisclosed injury that caused him to miss three games. He is 7-1-0 with a 1.74 goals-against average, a .941 save percentage and two shutouts this season.
"I just try to stay focused and not get too carried away," Rask said of being able to stay hot after missing time. "I think that's the biggest answer, best answer, I can give you."
WATCH: All Sabres vs. Bruins highlights
Boston forward David Pastrnak had a goal and an assist. His eight goals are tied with Chicago Blackhawks forward Artem Anisimov, Winnipeg Jets forward Patrik Laine and Pittsburgh Penguins center Sidney Crosby for the NHL lead.
Brad Marchand, David Krejci and Riley Nash scored for the Bruins (7-5-0), who have won four of five, and coach Claude Julien earned his 400th victory with Boston.
The Bruins went 3-for-8 on the power play after going 3-for-38 in their first 11 games.
"We just worked on it this morning and gave them the responsibility as some of our best players on the team that they had to step it up," Julien said. "So they did that tonight, and so a little practice this morning and obviously some pride tonight and making sure that they were difference-makers instead of ending up on the negative side."
Video: BUF@BOS: Nash credited with goal off Kulikov's skate
Goaltender Robin Lehner made 38 for the Sabres (5-5-3), who had won their previous three road games.
Boston outshot Buffalo 42-32, including 15-5 in the second period.
Marchand opened the scoring with a power-play goal at 5:44 of the second period. His wrist shot went off Lehner's mask and stick before trickling behind the goalie for a 1-0 Boston lead.
After a double minor for high sticking to Zemgus Girgensons at 7:50 and two minors to Jake McCabe at 9:16, the Bruins took advantage of an extended 5-on-3 power play when Krejci scored at 10:12 of the second for a 2-0 lead.
"It gets you out of your rhythm," Sabres captain Brian Gionta said about their penalty troubles. "Obviously, it gives them momentum, but the biggest thing is you're over-taxing your killers and not getting a good rotation when the guys are sitting down."
Nash got a fortuitous bounce to score his first goal of the season and give Boston a 3-0 lead. Matt Beleskey pressured Buffalo defenseman Dmitry Kulikov, who blindly sent the puck up the wall, and Nash intercepted and sent it toward the net, where it deflected past Lehner off Kulikov's skate at 14:41.
Pastrnak scored on the power play at 9:45 of the third period for a 4-0 lead.
Video: BUF@BOS: Pastrnak buries PPG off a rebound
Goal of the game
Krejci beat Lehner with a slap shot from the top of the left faceoff circle for his first goal of the season, ending a 15-game drought that dated to April 1, when he scored twice against the St. Louis Blues.
Video: BUF@BOS: Krejci blasts a massive slap shot for PPG
Save of the game
Rask stopped Gionta on a shorthanded breakaway with a blocker save at 13:02 of the second period.
Video: BUF@BOS: Rask turns away Gionta's breakaway chance
Highlight of the game
Rask made 14 saves in the third period, including with his glove on a William Carrier slap shot at 18:28, to cap his 32nd NHL shutout. He's in sole possession of third place on the Bruins' all-time shutout list.
Video: BUF@BOS: Rask robs Carrier with slick glove save
Unsung moment of the game
With the Sabres killing a penalty, defenseman Jake McCabe tried to clear the puck from the slot but was hit by Pastrnak. Marchand intercepted the puck and scored the first goal of the game.
Video: BUF@BOS: Marchand scores a PPG through traffic
They said it
"They were struggling on the power play, but they're a dangerous group. Even though they weren't scoring, you could see it in their power play. We just gave them too many opportunities to prove they were a good group." -- Sabres coach Dan Bylsma
"It's another number. So I move on from those. But it's great. Like I always say, it's something I guess I can cherish down the road. But right now, I just got to keep plugging away." -- Bruins coach Claude Julien on his 400th win with Boston
Video: BUF@BOS: Rask collects 32 saves to shut out Sabres
Need to know
Buffalo forward Sam Reinhart played his 100th NHL game. ... Sabres forward Tyler Ennis was limited to 7:33 of ice time because of injury, Bylsma said. ... Bruins forward Noel Acciari skated just one shift in the third period and left the game because of injury. Julien had no update after the game. ... Bruins goaltender Anton Khudobin, who was ruled out for three weeks with an upper-body injury beginning Oct. 25, has started skating but hasn't been handling a stick.
Sabres: Home against the Ottawa Senators on Wednesday (7:30 p.m. ET; SN, TVA Sports, MSG-B, NHL.TV)
Bruins: At the Montreal Canadiens on Tuesday (7:30 p.m. ET; SNE, RDS, NESN, NHL.TV)
Video: Bruins defeat Sabres behind Rask's shutout, 4-0