Joe Vitale added his first goal in more than a year for the Penguins, who have beaten the Bruins five consecutive times.
Tyler Seguin scored his 10th goal for Boston, and Tuukka Rask made 16 saves but couldn't stop the Bruins from losing to Pittsburgh for the second time in less than a week.
The Penguins scored three times in the final 7 minutes Tuesday to steal a 3-2 victory. There were no dramatics necessary this time, as hockey's hottest team never trailed to remain unbeaten in March.
Pittsburgh, which moved into first place in the Eastern Conference — two points ahead of Montreal — has allowed just five goals in five games.
SENATORS 4, JETS 1
OTTAWA (AP) — Jakob Silfverberg scored twice to lead Ottawa over Winnipeg.
Guillaume Latendresse and Kyle Turris added goals for the Senators (15-8-6), who got 25 saves from Robin Lehner.
Zach Bogosian scored the lone goal for the Jets (15-12-2). Ondrej Pavelec made 38 saves, but Winnipeg's three-game winning streak was snapped.
Trailing 2-0 heading into the third, the Jets finally beat Lehner at 3:26 as Bogosian's shot from just inside the blue line made it through traffic and just under the crossbar.
Evander Kane had a great chance to tie the game midway through the period on a 2-on-1 break, but was robbed by Lehner, who made a great pad save.
CAPITALS 5, SABRES 3
WASHINGTON (AP) — Troy Brouwer had a goal and an assist in the second period of Washington's victory over Buffalo.
Jason Chimera added his first regular-season goal in nearly a year for the Capitals (12-15-1), who broke out of an offensive slump in which they had scored only seven times in five games — losing four.
Alex Ovechkin got the Capitals going with his 350th NHL goal, scored only 19 seconds in, and Marcus Johansson and Matthieu Perrault also had a goal and an assist each as Washington beat Buffalo at home for the seventh time in eight games.
Cody Hodgson scored twice for the Sabres (10-15-4), who have lost five straight road games and have won just once in seven games overall. Brian Flynn added a goal the Sabres, who outshot the Capitals 30-25.
Washington busted out of its scoring slump with three goals during a 5:22 stretch of the second period.
OILERS 3, PREDATORS 2
EDMONTON, Alberta (AP) — Jordan Eberle had a goal and assist and Edmonton topped struggling Nashville.
Magnus Paajarvi and Lennart Petrell also scored for the Oilers (11-11-6), who have won three of four.
Shea Weber and Roman Josi had goals for the Predators (11-12-6), who have lost the first three games of a four-game trip.
The Oilers scored first in the second period and then added two goals in the third to win. Devan Dubnyk made 29 saves.