BOSTON — The Toronto Maple Leafs talked at length this week about the importance of trying to contain Boston's powerful top line in their first-round playoff series with the Bruins.
There's lots of work to be done in that department, and a host of others, after Thursday night.
The trio of David Pastrnak, Brad Marchand and Patrice Bergeron combined for six points as the Bruins thumped the Leafs 5-1 in the opener of their Eastern Conference quarterfinal.
"We've got to be better, obviously," said Toronto head coach Mike Babcock, who had Marchand and Bergeron when all three were part of Canada's team that won the World Cup of Hockey in 2016. "Give them credit, they were good.
"We weren't good enough."
Pastrnak had a goal and two assists, Marchand added a goal and an assist, and Bergeron set up one in a dominant performance that had the Leafs' heads spinning from the raucous opening faceoff onwards.
"They played with a lot of speed," Toronto defenceman Morgan Rielly said. "The building was rocking, they were feeling the energy."
David Krejci, with a goal and an assist, David Backes and Sean Kuraly rounded out the scoring for Boston, which got 26 saves from Tuukka Rask. Torey Krug added two assists.
Zach Hyman replied for the Leafs, while Frederik Andersen made 35 stops.
Game 2 goes Saturday at TD Garden before the series switches to Air Canada Centre.
The Leafs may be without forward Nazem Kadri for Game 2. He has a hearing scheduled Friday with the NHL department of player safety after he charged Boston forward Tommy Wingels in the third period of Thursday's game.
Kadri took exception to an elbow to Mitch Marner from Wingels and replied by taking a run at the Boston forward after he tumbled to the ice, earning a five-minute major for charging and a game misconduct in the process.
"I just felt like he made contact with Mitchy's head to start, and I didn't see a call there," Kadri said. "He was turning up the wall so I was committed to the hit, and then he ended up falling. It happened pretty quick.
"It's in the hands of the NHL."
Marchand, Pastrnak and Bergeron — who totalled 99 goals in the regular season and are stellar in all three zones — set the tone early with their skating and physical play.
Bergeron said an emphasis on communication between the three has been crucial to their success.
"Every time we come back to the bench we talk about what we saw and what we can do better," said the veteran centre. "That's been key to creating that chemistry."
Boston limited space in the neutral zone at even strength all night long as Marner, Auston Matthews and William Nylander struggled to find room.
Toronto's power play, which had been operating at 32.2 per cent since the end of January, will also be a point of emphasis after going 0 for 3, while the penalty kill allowed Boston to score three times with the man advantage.
"Outscored 3-0 (on) special teams ... that's most likely never going to get it done," Leafs defenceman Ron Hainsey said. "It seemed like we spent a vast majority of the game on our half of the ice."
Backes snapped a 1-1 tie on the power play at 15:43 of the second when he chipped a loose puck up and over Andersen.
The Bruins' second goal with the man advantage came after the Leafs wasted two power-play chances of their own, including one where Marner slid a puck across the face of a wide-open net.
Boston stretched its lead to two with 38 seconds left in the period when Pastrnak took a feed from Marchand and zipped a shot past Andersen's glove.
Marchand was at his agitating best earlier in the period when he nudged Leafs defenceman Nikita Zaitsev into Andersen to draw a crowd, and licked Leo Komarov's face in the first — the second time that's happened this season.
"That was weird," Kadri said. "That was very weird to me.
"It's agitating at that point. It's certainly uncomfortable to watch."
Toronto killed off two penalties to start the third, but Kuraly made it 4-1 when he batted the puck out of mid-air at 7:41.
After Kadri was tossed for the hit on Wingels, Krejci rounded out the scoring from a horrible angle on the power play at 11:29.
Boston grabbed the lead on the power play at 5:28 of the first when Krug set up Marchand, but Hyman tied it on a great individual effort at 16:52.
"It's a long series," Rielly said. "We've got lots of areas we can get better in, things we can improve on."
Both bounced in the opening round of last season's playoffs, Boston and Toronto came into the series with big expectations, and with the knowledge one team will be left bitterly disappointed at its conclusion.
The Bruins finished the regular season with 112 points, good for second in the Atlantic Division and fourth in the overall standings. The Leafs, meanwhile, wracked up a franchise-record 105 points, which earned them the division's third seed and the league's seventh-best record.
Toronto and Boston last met in the playoffs in 2013, a series that saw the Leafs become the first team in NHL history to blow a three-goal lead in the third period of a Game 7 before the Bruins eventually won it in overtime.
There's been plenty of turnover on both sides since, but Boston's core — including Marchand and Bergeron — that made it all the way to Stanley Cup final that year remains largely intact.
Matthews had four goals to lead the Leafs during their six-game defeat to Washington last spring, a series that gave the superstar centre and his young teammates a first taste of playoff hockey at this level.
They got another lesson Thursday about what it takes to win at this time of year.
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