Reimer, who'd been out with concussion-like symptoms, made his first start since October 22 and looked sharp with 26 saves.
However, four shots got past him, and Boston backup goaltender Tuukka Rask took advantage of his only start of the week with 21 saves as the Bruins improved to 4-0-0 against the Leafs with a 4-1 win at the TD Garden.
The Bruins are now 13-0-1 since the start of November and lead the Leafs by three points in the Northeast Division. They have outscored Toronto 23-6 in the four games.
"It was good to get back in there, but it wasn't exactly the result we were looking for, or I was looking for," Reimer said. "I thought we played pretty well as a team. I thought we had a lot of good chances. The way I see it, Rask outplayed me today. That frustrates me more than anything. … But I thought the guys fought hard, they blocked a lot of shots for me, they worked their butts off."
If the Leafs worked their butts off, the Bruins did so much more. During the third period, when they extended to a 4-1 lead from 2-1 up at the second intermission, the Bruins outshot Toronto 11-4. During one stretch that ended with a Leafs icing and a timeout, Boston pinned the Leafs in their own zone for more than two minutes with the line of David Krejci, Nathan Horton and Milan Lucic doing work down low and the defensive pair of Joe Corvo and Andrew Ference keeping the puck in at the points and along the walls.
"It was a real good shift. I thought they did a great job," Bruins coach Claude Julien said. "David eventually came off as the third man high and we were able to put a fresh guy [Patrice Bergeron] out there and sustain the pressure. That was a real good shift for us in the third period. (Horton) and (Lucic) are such strong individuals that they're hard to knock off the puck. When they feel like they want to protect the puck and they want to be strong on it, we can certainly spend a lot of time in the offensive zone playing that way."
Chris Kelly had given the Bruins the lead with 6:49 left in the second period. Johnny Boychuk's blast from the high slot beat Reimer for an insurance goal 3:06 into the third. Horton, who along with Lucic and Krejci enjoyed a two-point night, provided the final margin with a goal with 5:34 remaining in regulation.
The Bruins' defensive effort in front of Rask included keeping NHL leading scorer Phil Kessel off the scoresheet and limiting him to just five shots on net. Rask snuffed out Kessel's lone Grade-A scoring chance – a second-period breakaway when the game was still just 2-1.
"The puck was kind of bobbling a bit. [Our defenseman] was doing a pretty good job skating in between and taking that passing lane away, so I had a good chance to challenge him a little bit," Rask said. "He couldn't get a real good shot off that, but it hit my stick or something I guess."
Boston, which entered the game with the sixth-best home penalty kill in the League, also managed to stifle Toronto's streaking power play. The Leafs had scored at least one power-play goal in eight straight games before getting shut out on four opportunities by the Bruins.
"They did a pretty good job on our power play. We took some ill-advised shots," Toronto coach Ron Wilson said about the struggles of his second-ranked power play. "They rushed us into some things that we didn't want to do. But if we had scored one goal on the power play it wouldn't have made any difference."
Julien said his team stuck to the game plan to keep the Leafs from gaining the special-teams edge.
"We talked about being very disciplined tonight. Those calls that were made -- I'm not saying they were bad calls, but they were really borderline and they chose to call those, so I can't criticize our team for lacking discipline," he said. "But our PK came out there and did a great job and Tuukka made the saves when he had to. We put a lot of pressure up the ice and didn't make it easy for them to enter our zone."
Once winners of 10 in a row, the Bruins have now bounced back since their shootout loss to Detroit last Friday with three straight victories, including their home-and-home sweep of the Leafs.
"It's a great feeling, it's so much fun," Krejci said. "There is nothing better than that, we are having fun. Everything is going our way right now."