TORONTO -- The Toronto Maple Leafs won this one for their city.
The victory came hours after 10 people were killed when a van drove onto a sidewalk in Toronto's north end and struck multiple pedestrians. Most of the players woke from their pregame naps to learn of the incident at 1:30 p.m. that also injured 15 people.
"We're sending all our love," said Maple Leafs forward Mitch Marner, who scored the tiebreaking goal and added an assist. "This is a big win for us after an emotional day."
There was a moment of silence for the victims and their families prior the opening faceoff at Air Canada Centre.
"Very tragic event," Bruins forward Brad Marchand said.
William Nylander and Tomas Plekanec also scored for Toronto. Nikita Zaitsev added two assists, and Plekanec also had one. The Maple Leafs, who trailed the series 3-1 before winning two straight, were behind 1-0 early in the second period of this one.
Game 7 is Wednesday night in Boston with the winner advancing to face Tampa Bay in the Eastern Conference semifinals..
Scoreless after an end-to-end first period, the Bruins grabbed a 1-0 lead 1:02 into the second when David Krejci won a faceoff after an icing against Auston Matthews right to DeBrusk, beat Andersen between his arm and body.
Toronto responded just 35 seconds later when Nylander buried a rebound of Jake Gardiner shot from the point for his first goal of the playoffs.
The Leafs appeared to go ahead at 3:04 when Zach Hyman beat Rask with a no-look backhand as he fell to the ice. The Bruins challenged the play for goalie interference, and replays showed the forward knocked the stick out of Rask's hands as he cruised through the crease just before scoring.
Boston appeared to control the play after that as Toronto could barely get out of its own zone or complete a clean breakout. Andersen -- who recorded 42 stops in a 4-3 victory in Game 5 on Saturday -- made great saves off Rick Nash, Marchand and Patrice Bergeron to keep things even.
"Just enjoying the moment," Andersen said of the turnaround in his play. "Being in a do-or-die position, I think we all embrace that as a team."
The Maple Leafs, however, wend ahead with 6:35 left in the period when Marner was quickest to a loose puck in the slot and beat Rask with a backhand to the far post after Marchand couldn't clear.
Toronto killed off its first penalty early in the third, and was then left fuming when David Backes elbowed Andersen in the mask, but was only assessed an offsetting roughing minor when Roman Polak came to his goalie's defence.
The Leafs couldn't connect on their third power play moments later, and Andersen stoned Sean Kuraly with under 10 minutes to go.
Rask then robbed Nylander off a great feed from Auston Matthews.
The Bruins went back to the power play with under six minutes left, but the best chance came when Rask stopped Kasperi Kapanen on a 2-on-1 that turned into a breakaway before stoning Krejci on a one-time shot that brought the towel-waving crowd to its feet.
Rask followed that up by stopping Matthews on another 2-on-1 off a pass from Plekanec before Plekanec sealed the win with an empty-netter with 1:14 to play.
"Give them credit, they protected their house," Bruins coach Bruce Cassidy said.
Both goalies were on their game in the first as the clubs combined for 27 shots on goal, including 17 from Boston.
Andersen made a nice stop on Nash less than two minutes in after a Maple Leafs turnover before Rask, who allowed four goals on 13 shots before getting pulled in Game 5, fought off Zaitsev's point shot.
Marchand came close when his shot off another turnover struck the inside of Andersen's pad and bounced out the other side.
Rask held the fort on the game's first power play, and Andersen followed up with his second incredible stick save of the series when he swatted a Backes attempt from in tight with Nash lurking.
The Maple Leafs fell behind the Bruins 3-1 the last time the clubs met in the playoffs back in 2013 before tying the series 3-3 with back-to-back 2-1 victories. Toronto then became the first team in NHL history to blow a three-goal lead in the third period of a Game 7 as the Bruins stormed back from a 4-1 deficit and won 5-4 in overtime. ... Coming into these playoffs, teams that take a 3-1 lead in a best-of-seven series hold an all-time record of 270-28 -- good for a success rate of 90.6 per cent. ... The Maple Leafs have trailed 3-1 in a best-of-seven series 15 times, with their only victory coming in the 1942 Stanley Cup Final when they stormed back from a 3-0 deficit to beat the Detroit Red Wings.