Minus the suspended Shawn Thornton, awaiting his punishment for his takedown that sent Penguins defenseman Brooks Orpik to the hospital on Saturday, the injury-ravaged Bruins rallied to defeat the Maple Leafs 5-2.
Carl Soderberg, Torey Krug, Kevan Miller, Jarome Iginla and Patrice Bergeron scored for Boston.
Thornton, the Bruins' enforcer, is suspended pending a league hearing into the incident.
For Iginla, Sunday's game was a chance for the Bruins to get back to their game.
"It was (good)," he said. "Just to get the focus on just winning a game and playing. Because, yeah, it was pretty emotional. Everybody felt that from (Saturday) night."
The Bruins were also without the injured Loui Eriksson and Chris Kelly, among others.
Defensemen Adam McQuaid and Johnny Boychuk were sidelined with earlier injuries.
And the Bruins' defensive issues were intensified Sunday when Dougie Hamilton left after the first period with a lower-body injury after a collision with Leafs defensemen Carl Gunnarsson.
Boston coach Claude Julien said Hamilton was scheduled to return home Monday for medical evaluation, but was hopeful that Boychuk might be close to returning to the lineup in his absence during the remaining three games of the Canadian road trip.
Peter Holland and Jay McClement scored for Toronto. The Leafs led 1-0 in the first and then cut the lead to 3-2 early in the third before Boston scored two late goals.
Julien attributed his team's success to the organization's focus on playing a two-way game, whether it be wearing a Boston or AHL's Providence jersey.
"The way we play is a very demanding way of playing but we feel our scouts and upper management have done a good job of giving us the types of players who can play that game," he said.
"So even with the guys being called up, they play a very similar style back in Providence. And we're asking them to do the same thing here.
"It's about believing what your team's all about. Going out there and doing it, whether you're a young player or an older player. Our game can never change."
The Leafs, who beat Ottawa 4-3 in a shootout Saturday, controlled the early going and led 1-0 after the first. But the Bruins had a three-goal outburst in the second period, including a pair of power-play goals in a 93-second stretch.
"The first period it seemed like we had our legs, we were doing a lot of things," Toronto coach Randy Carlyle said. "Then we take the one penalty and their (tying) goal kind of flattened us and the next thing you know we're killing (a penalty) again right after. And it was bang-bang, all of a sudden they scored two goals and the life went out of our hockey club."
Toronto, which also gave up two power-play goals against the Senators, went 0 for 4 on its power play Sunday. The Bruins, who had to kill off a pair of penalties in the third, outshot the Leafs 39-32.
The focus before the game was on Thornton's play on Saturday.
"I agree, he did cross the line," Julien said. "He got caught in the emotions. There's nobody that's proud of what happened (Saturday) night. Absolutely not. So he's going to suffer the consequences and so will we."
"Thorny did cross the line and some others did too," Julien added. "But sometimes you have to man up to those things and I think he did."
Julien saw a woozy Miller leave the game later after being crunched into the boards by Leafs captain Dion Phaneuf. The Boston coach said he asked the referee whether it was a penalty.
"It's very minor and should impact him playing for us next game but it was a close call — head first into the boards," Julien said.
The Leafs faced Chad Johnson, who was filling in to give Bruins No. 1 goalie Tuukka Rask a night off. Jonathan Bernier started for Toronto, after James Reimer's 47-save performance in Ottawa.
It took the Leafs almost five minutes to get a shot on Johnson, but they went ahead at 12:20 when Holland jammed a David Clarkson redirect of a Jake Gardiner shot into the net for his third of the season.
Boston pulled even on the power play at 5:14 of the second period after Reilly Smith found Soderberg alone on the edge of the crease. Toronto's Carter Ashton was in the penalty box for delay of game.
Shortly after the goal, the Leafs went a man-down again with Gunnarsson sent to the box. And Krug made the Leafs pay with his eighth goal of the season at 6:47, beating Bernier with the hulking Zdeno Chara blocking the goalie in front.
Ten of the Bruins' 15 power-play goals this season have come from their defensemen.
Boston outshot Toronto 8-0 in the second period before the Leafs put a shot on Johnson at 9:57. Defenseman Cody Franson had a good chance from in close with seven minutes remaining but the Bruins goalie made the save.
Phaneuf and forward Phil Kessel ran into each other on a line change, flooring Kessel. It was that kind of period for the Leafs.
Smith hit the Toronto crossbar late in the period. Seconds later, Miller's wrist shot from the blue line slipped through Bernier at 15:58. It was his first NHL goal.
Boston outshot Toronto 17-9 in the second period.
McClement closed the gap to 3-2 just 37 seconds into the third, winning a faceoff in the Bruins' end and then driving the Boston goal and slapping in his own rebound for his first of the season.
The Bruins had to kill off consecutive penalties to maintain their lead. The Leafs needed a huge save from Bernier on Jordan Caron to stay within one as the clock wound down.
But Bernier was powerless to stop Iginla after Milan Lucic accelerated past Phaneuf and passed to Iginla in the crease for his sixth goal at the 16:00 mark.
NOTES: The Bruins continue their four-game road trip in Canada against Calgary on Tuesday, Edmonton on Thursday and Vancouver on Saturday before returning home to host the Flames on Dec. 17.