That ends Boston's losing streak at two games as they still have not lost three straight since October.
Jordan Caron followed up his first two-point game on Sunday with his first three-point effort with two goals and an assist. That helped propel Boston to its fifth win over Toronto in as many tries this season. The Bruins have outscored the Leafs 28-10 in those five games.
Boston returns home to face the Sabres on Thursday.
Third Period, 19:43, Bruins 5-4: The Bruins will have to survive the final seconds down a man as Chris Kelly is called for delay of game for clearing the puck over the glass.
Third Period, 18:41, Bruins 5-4: The Leafs have pulled Gustavsson for the extra attacker looking to tie this one in the closing minutes.
Third Period, 16:54, Bruins 5-4: The Bruins come up with a huge penalty kill there, keeping the Leafs without a shot on that man advantage before Chara was freed from the box.
Third Period, 14:54, Bruins 5-4: The Bruins will now be shorthanded as Zdeno Chara is called for boarding Tim Connolly. Toronto goes on the power play with a chance to tie the game.
Third Period, 13:13, Bruins 5-4: The Leafs pull within one as Mikhail Grabovski takes advantage of a defensive breakdown for a partial breakaway.
He came down the right side and beat Thomas up high inside the near post.
Third Period, 8:30, Bruins 5-3: The Bruins come up empty on that power play and almost gave up a shorthanded tally as the Leafs had a 2-on-1 chance.
Third Period, 6:30, Bruins 5-3: Thomas makes a save and gets a snow shower from Matt Lombardi, which draws a crowd. Adam McQuaid and Tyler Seguin take particular exception and get in Lombardi's face for his breach of etiquette.
Lombardi gets called for unsportsmanlike conduct for his antics as the Bruins go back on the power play.
Third Period, 2:38, Bruins 5-3: The Bruins miss a chance to pad the lead as Seguin comes down the right side and sets up Lucic on the left. Lucic put it behind Gustavsson, but fired wide of the net.
Third Period, 2:00, Bruins 5-3: The Bruins created some chances but couldn't convert the power play as the sides return to even strength.
Third Period, 0:00, Bruins 5-3: The final frame is under way in Toronto. The Bruins open on the power play as Tim Connolly got an extra minor for cross-checking in addition to the matching roughings with Brad Marchand at the end of the second.
Second Intermission Notes: The Bruins finally look like the Bruins again. All it took was playing the Leafs for the first time in three months. Boston broke out offensively with four goals and also engaged in a trio of scraps to take a 5-3 lead into the third.
Jordan Caron continues to dazzle. He now has two goals and an assist and is a plus-3 with four shots in 9:10. He had five points in his first 30 games, and now has five points in his last five periods.
The Bruins have outshot Toronto 24-17 despite continuing to miss their target often. They have 10 missed shots to none for Toronto and are up 45-26 overall in shot attempts. The hits continue to pile up as well, with the Bruins leading 32-29 in that category. There was plenty of legitimate physical play too, with Shawn Thornton taking on Jay Rosehill in a lengthy heavyweight scrap, Dennis Seidenberg surprising Colby Armstrong in a one-sided bout and Brad Marchand having a quick scrap with Tim Connolly at the buzzer. That last one drew just roughing minors.
Joffrey Lupul did not return after being hurt on a David Krejci check, while Benoit Pouliot did not play in the second half of the second for the Bruins either.
End Second Period, Bruins 5-3: A wild second period comes to a close with more bad blood as Brad Marchand and Tim Connolly drop the gloves.
Connolly took exception to Marchand finishing his hit late and they wrestled a bit before Connolly scored the takedown with a hip toss.
Second Period, 16:09, Bruins 5-3: The Bruins strike again, this time with Tyler Seguin scoring to extend the lead to two goals for the first time.
Seguin one-timed a blast from the right slot off a feed out of the right corner by Milan Lucic. That's Seguin's second of the night, as Chara's earlier goal was changed to Seguin for a deflection earlier this period.
Second Period, 13:34, Bruins 4-3: The Jordan Caron Show continues as the youngster scores again to put the Bruins back ahead.
Zdeno Chara came in down low on the left side and passed across the crease to Caron for an easy tap-in at the right post.
Second Period, 10:56, 3-3: The Bruins kill off the second penalty, with Bergeron exiting the box to put the sides even. But the score is also even now that the Leafs converted the 5-on-3 chance.
Second Period, 9:52, 3-3: The Leafs tie it on the two-man advantage as Phil Kessel scores.
Kessel fired in a shot from the left circle that Thomas stopped initially, then knocked over the line himself. The Leafs remain on a 5-on-4 power play.
Second Period, 8:56, Bruins 3-2: The Bruins will be down two men for 1:40 as Patrice Bergeron is called for tripping.
Second Period, 8:36, Bruins 3-2: The gloves come off again with Dennis Seidenberg the unlikely combatant for the Bruins. He took exception to a run at him by Colby Armstrong. Adam McQuaid dropped the gloves and tried to go after Armstrong, but Seidenberg took care of it himself and dropped Armstrong with a series of rights.
McQuaid gets the extra minor for roughing to give Toronto a power play.
Second Period, 7:34, Bruins 3-2: The Bruins are outshooting Toronto 8-3 in the second, as they have taken over momentum after that quick power-play strike by the Leafs.
Toronto also lost Joffrey Lupul, who went to the locker room in pain after taking a big hit from David Krejci.
Second Period, 2:45, Bruins 3-2: The gloves come off right off the faceoff following Kelly's goal, as Shawn Thornton squares off with Jay Rosehill.
Both go with rights and land plenty in a long scrap. Thornton is bleeding as the stitches he was already sporting got opened up, but he appeared to land the better shots in his NHL-leading 18th fight of the season.
Second Period, 2:43, Bruins 3-2: The Bruins take their first lead of the night with their second goal in less than a minute.
Caron was the catalyst again, driving the net from the left wing, with Chris Kelly following up with the shot from the top of the crease.
Second Period, 2:02, Leafs 2-2: The Bruins answer right back as Zdeno Chara ties the game again.
Chara took a pass off the right boards and weaved throigh the defense, driving to the net and beat Gustavsson up high.
Second Period, 0:57, Leafs 2-1: The Leafs take advantage of the penalty as John-Michael Liles scores on a rebound from the right slot.
Phil Kessel had the initial shot from the left circle, with Liles pinching in from the point to clean up the second-chance opportunity.
Second Period, 0:31, 1-1: The Leafs get the first power play of the night as Brad Marchand is sent to the box for a very marginal hooking call.
Second Period, 0:00, 1-1: The middle frame is under way with the Bruins and Leafs tied heading into the second 20 minutes in Toronto.
First Intermission Notes: The Bruins bounced back from a bit of a slow start, taking over play late in the first and pulling even at 1-1.
Jordan Caron had the goal, which followed several strong shifts for the youngster. After struggling much of the season, he's been very pleasant the last couple games, following up his two-point performance Sunday in New York with another goal here. With their injuries up front, the Bruins need some new sources of offense.
Boston ended up out shooting Toronto 12-7 in the first. As usual though, the Bruins attempted even more shots than they put on net, with eight more blocked and seven missing. The Leafs had just five blocked and none missed, as the Bruins had 27 attempts overall to just 12 for Toronto.
It wasn't a very physical frame with no penalties called, but the stat keepers still found a way to credit the teams for 34 hits (17 each). Lane MacDermid has a game-high five so far.
End First Period, 1-1: The opening period comes to a close, but not before the Bruins mount one final threat in the closing seconds with Tyler Seguin hitting the post from the low slot.
First Period, 18:20, 1-1: The Bruins have settled things down after Toronto's initial burst to start the game. It's been pretty even with limited chances since, with the Bruins taking advantage of one to pull even.
First Period, 15:16, 1-1: For the second time in the period, play is stopped when one of the stanchions on the glass in the Boston zone comes loose.
First Period, 13:58, 1-1: Jordan Caron gets another chance and buries this one to tie the game.
Joe Corvo sent in the initial shot from the left point and Benoit Pouliot shoveled the puck back out from from the side of the net, with Caron able to tap it home from the top of the crease.
First Period, 10:43, Leafs 1-0: Jordan Caron with an impressive shift as he builds off the confidence gained from his goal and assist Sunday against the Rangers.
He was at the right point covering for Boychuk when he found Boychuk at the left post for a good scoring chance. Caron then drove down the slot for a bid of his own, but neither man connected as it remains 1-0.
First Period, 8:34, Leafs 1-0: The Bruins show some signs of life with some possession time in the Toronto end, then a nifty drive through the defense for a chance at the left post by Brad Marchand, but Gustavsson makes the stop.
First Period, 6:29, Leafs 1-0: The Leafs continue to pressure, forcing Thomas to make a stop on Matt Frattin driving the net, then Clarke MacArthur had a chance in front.
First Period, 3:01, Leafs 1-0: The Leafs strike quickly, with Carl Gunnarsson opening the scoring just over three minutes into play.
Gunnarsson pinched in from the point and fired home a shot up high past Thomas from the high slot.
First Period, 0:00, 0-0: The Bruins' final visit to Toronto this season is under way, with the Leafs taking the ice at home for the first time with Randy Carlyle behind the bench.
7 p.m.: The Bruins will open with their top line of Milan Lucic, David Krejci and Tyler Seguin, with Zdeno Chara and Johnny Boychuk on defense and Tim Thomas in goal.
The Leafs counter with their new checking line of Tim Connolly, David Steckel and Nikolai Kulemin up front, Dion Phaneuf and Carl Gunnarsson on the blue line and Jonas Gustavsson in net.
6:55 p.m.: The Bruins have scratched Mike Mottau again, sticking with the same defense used since Johnny Boychuk returned on Saturday.
Mottau is the only healthy scratch, with Daniel Paille (upper body), Andrew Ference (lower body), Rich Peverley (knee), Nathan Horton (concussion) and Tuukka Rask (groin) all out injured.
The Leafs have scratched Mike Brown (hand), Cody Franson and Joey Crabb.
6:30 p.m.: No surprise in the warm-ups, with Tim Thomas leading the Bruins out. He'll get this, and most of the rest of the year's starts.
Jonas Gustavsson led the Leafs out and will start in net for Toronto.
6:20 p.m.: Bruins general manager Peter Chiarelli met with the media moments ago in Toronto to discuss the Bruins goaltending situation.
He stated that Tuukka Rask will likely be sidelined closer to the six-week end of the 4-6 week prognosis for his groin injury.
Chiarelli also sees it as a "50-50" chance that Marty Turco will get through waivers. The backup plan for a backup goalie would be to wait for Anton Khudobin, who Chiarelli said is about two weeks away from returning from a wrist injury.
6 p.m.: The Bruins have lost three games in a row just once all season, with that skid coming all the way back in October.
In about an hour, they'll take on Toronto hoping to avoid dropping three straight again after back-to-back losses to the Islanders and Rangers over the weekend.
The Bruins have dominated the Leafs this season, winning all four previous matchups by a combined 23-6. But Toronto now has Randy Carlyle behind the bench, and will be fired up for the new coach's home debut.
8 a.m. ET: The Bruins will look to end a two-game skid against a club that has proven a cure for all of Boston's ills so far this season.
The B's pay their final visit to Toronto this season on Tuesday, having won the first two meetings with the Leafs at the Air Canada Centre 7-0 on Nov. 5 and 6-3 on Nov. 30. The Bruins also triumphed over Toronto at the Garden, winning 6-2 on Oct. 20 and 4-1 on Dec. 3. That puts the Bruins at 4-0-0 so far in the season series, outscoring their Northeast Division rivals 23-6.
But both teams are dramatically different than the clubs that faced each other in those meetings. Boston is mired in a stretch of mediocrity dating back to mid-January, going 10-12-2 in that span with back-to-back losses to the Islanders and Rangers over the weekend. The Bruins have been hit hard by injuries, with Nathan Horton (concussion), Rich Peverley (knee), Andrew Ference (lower body), Daniel Paille (upper body) and Tuukka Rask (groin) all currently sidelined.
The Leafs are a much different team as well, having fired coach Ron Wilson on Friday. Randy Carlyle, who led Anaheim to the Cup in 2007, took over behind the bench and the Leafs won 3-1 in Montreal in his debut on Saturday. That snapped a 1-9-1 skid, and the Leafs will be fired up to make Carlyle's home debut just as successful.
Toronto maintains a slim hope of reaching the playoffs for the first time since 2004, though the Leafs are five points, and four teams, out of the final playoff spot in the East in 12th place at 30-28-7 (67 points).
The Bruins (38-23-3, 79 points) are looking to secure their hold on the Northeast Division lead, which is down to just three points over Ottawa, albeit with three games in hand on the Senators.
The puck drops at 7 p.m., so check back here for updates on all the action.