TORONTO — After a flying start in front of a raucous home crowd, the Maple Leafs looked well on their way to finally getting over the hump against an opponent that's caused them so much heartache.
The thing about veteran teams, however, is they don't tend to go away quietly.
Down 1-0 in the first period of Sunday's Game 6, the Bruins scored off a lucky deflection on a man advantage before Boston's red-hot power play struck again.
The battle-tested visitors had counterpunched. Toronto didn't have much of a response until it was too late.
And now the Leafs need a third road victory in this back-and-forth Eastern Conference quarterfinal to advance to the second round of the playoffs for the first time since 2004.
Brad Marchand had two goals and an assist as Boston staved off elimination with a 4-2 victory over Toronto to force Game 7 at TD Garden on Tuesday night — the final act of a series where neither side has managed back-to-back victories.
"We were really ready, we were jumping big time," Leafs head coach Mike Babcock said. "As soon as we had a little adversity and they scored twice, we didn't recover.
"I don't know if the emotions got the better of us, but we couldn't get 'er back in check."
Torey Krug and Jake DeBrusk also scored for Boston, which got 22 saves from Tuukka Rask. David Pastrnak added two assists for the Bruins, who downed the Leafs in seven games in the first round of the 2013 playoffs, and again at the same stage of last spring's post-season.
"We've got a lot of character," Marchand said of his team's demeanour after falling behind. "We weren't fazed."
Morgan Rielly and Auston Matthews had the goals for Toronto, while Frederik Andersen stopped 37 shots.
"We've still got a good chance to win this series," Leafs centre John Tavares said. "That's what our focus is on."
Tuesday's victor will take on the Columbus Blue Jackets after the conference's eighth seed swept the Presidents' Trophy-winning Tampa Bay Lightning, who tied an NHL record with 62 victories in the regular season, in stunning fashion.
Toronto, which took a 3-2 lead in the series thanks to a patient, stifling defensive performance Friday at TD Garden, is Canada's last hope of ending the country's 26-year Stanley Cup drought. The Calgary Flames and Winnipeg Jets were eliminated from the playoffs earlier in the week.
"It's all small details," Matthews said of what's been the difference in a series where the road club has a 4-2 record. "Neither team's really making many mistakes.
"Our first five, six minutes was good and then their power play got them going, and then we didn't really have an answer until the third."
Sunday's 3 p.m. ET puck drop was something different for the Leafs, who had just one afternoon game on the 2018-19 schedule. The Bruins, meanwhile, took part in 12 afternoon contests.
Down by two through 40 minutes, Matthews scored his fifth goal in the last four games when he rifled a shot far side on Rask at 4:15 to ignite the crowd of 19,683 at Scotiabank Arena.
The 21-year-old was held without a point in the first two games, and had just a pair of points in Toronto's seven-game loss to Boston last spring.
Rielly then set up Matthews on another terrific chance only to see his pass hop over the star centre's stick as Toronto turned up the pressure.
Andersen bailed Rielly out after a brutal turnover with under four minutes to go, robbing Pastrnak of a chance that would have sealed it, but Marchand scored into an empty net with 1:54 left to force Game 7.
"We had a good attitude going into the third and started executing a little better," Tavares added. "We've just got to continue to be patient. We got within one.
"Unfortunately we couldn't find a third."
The Bruins led 2-1 after the first and had the Leafs on their heels early in the second, holding a 21-7 edge in overall shots through seven minutes.
DeBrusk stretched Boston's advantage to two when he left the puck for David Krejci on a 2-on-2 rush before getting inside on covering Leafs winger Andreas Johnsson and making a diving stab at the return feed at 7:57.
The goal was the first of the playoffs for DeBrusk, who scored six times last spring — with five coming against Toronto, including two in the clincher.
"I liked our (game), but obviously we're desperate," Bruins head coach Bruce Cassidy said. "This is the kind of thing we talked about, trying to hit our ceiling.
"We got as close I've seen in a long time."
The Leafs went up 1-0 at 9:42 of the opening period on Rielly's first of the playoffs. Having hit the post on an early power play, the defenceman blasted a one-timer shortside along the ice.
The Bruins tied it on a man advantage 1:41 later when Marchand snapped his third on a shot off a scrambled draw that hit Leafs defenceman Ron Hainsey and beat Andersen between the legs.
Held in check in Game 5, but still 5 for 14 coming into Sunday, Boston's power play struck a second time with 2:58 left in the period when Krug collected a rebound and ripped a shot upstairs on Andersen as the Bruins gained the upperhand — one they wouldn't relinquish.
"We've got a one-game series against these guys," Babcock said looking ahead to Tuesday. "We've got a good group that enjoys being together and plans on having a good run.
"In order to do that, we've got to go into Boston and win a game."
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