BOSTON -- This was not the Boston Bruins team that has been inhabiting TD Garden for the past couple of months, a team that picked itself up at the All-Star break and became a dynamo. This was not the smart, competent, defensively stingy team that watchers have come to expect. This was a team that was slow and sloppy, that mismanaged the puck, that allowed breakaways to an opponent that loves to take advantage of them.
And so it wasn't a surprise that the Bruins lost Thursday at TD Garden, 4-1 at the hands of the Toronto Maple Leafs, a team that the Bruins have bested in each of their past two matchups in the Stanley Cup Playoffs, including an epic seven-game series last season.
It was what they earned, and now they find themselves trailing in the best-of-7 series with Game 2 at TD Garden on Saturday (8 p.m. ET; NBC, CBC, TVAS).
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"I think maybe we thought it was going to be a little bit easier than it was out there," forward Brad Marchand said. "We were trying to play too much of a controlled style, where that's not really our game. So we've just got to play a little faster."
This is a Maple Leafs team that forces mistakes using its speed, a team that can put opponents off their game. The Bruins had managed it in the regular season, winning three of four games, and had managed it well enough in the past.
But they didn't Thursday.
Perhaps that was a matter of taking Toronto too lightly, as Marchand mentioned. Perhaps the Bruins, given their past success against the Maple Leafs and the way they steamrolled through the second half of the season, thought that a spot in the Eastern Conference Second Round was their birthright.
If they did, they should no longer think that way. They can no longer think that way.
"I don't think they took us off our game; I just don't think we played our game," Marchand said. "We weren't playing the right way the whole way through, weren't taking care of pucks the way we normally do and the way we can. That's what they thrive on."
The Bruins were able to take the lead, with Patrice Bergeron scoring on the power play at 9:31 of the first period, but it quickly went downhill from there. Mitchell Marner scored the first of his two goals at 16:44 of the first, cleaning up a rebound. His second came on a shorthanded penalty shot at 2:47 of the second.
Video: TOR@BOS, Gm1: Marchand sets up Bergeron for PPG
William Nylander then made it a two-goal advantage at 18:25 on one of the numerous breakaways the Bruins allowed, especially as the game wore on.
As Bruins coach Bruce Cassidy put it, "We've been exposed by them on those breakaways, and you give up two, three in a row that period, so shame on us."
It wasn't their only issue.
"Obviously a lot of stuff we didn't do tonight," Bergeron said. "It was nothing we didn't expect, I guess. They're a team that works hard and gets their chances by putting the puck on net and converging. I think we didn't take care of the blue lines, that's where we got caught many times, and against a team like them, they're going to capitalize and get some momentum out of it."
Cassidy suggested some of the problems came from having relatively young defensemen, with Brandon Carlo and Connor Clifton each playing in his first Stanley Cup Playoff game. But Charlie McAvoy had played in 18, and Matt Grzelcyk had played in 11, and just as many issues were coming from Zdeno Chara -- veteran of 159 NHL playoff games heading into Thursday -- as the young players.
"Other guys tried to force it a little bit," Cassidy said. "Maybe turn down some opportunities to make an easier play, especially in the offensive end of it, offensive blue line, opportunity on the 2-on-1 we had with [Grzelcyk]. Next thing you know, it's in our net, so some of that hopefully they've learned that you have to make a quicker decision with it. … They've got a fast team, so that shouldn't be a surprise.
"Clearly on us to get that message across better Saturday."
Video: TOR@BOS, Gm1: Marner pots second goal on penalty shot
The message has to be to take care of the puck better, to force the Maple Leafs to skate and to defend.
"Our puck management issues today cost us in a lot of different areas in the game, and whether it was us or them or a combination of both -- you can dissect it any way you want -- it really had an effect on giving them a lot of energy both with their legs and physicality," Cassidy said. "We just have to be better in that area."
The Bruins will take a hard look at their play on Friday, ahead of Game 2. They will try to address their areas of vulnerability, their areas of concern, whether that will necessitate a shuffling of the personnel, or simply a revision of their expectations.
Because there should be no surprises. No taking anyone lightly.
Now it's up to the Bruins to clean up their act, to manage the puck better, to eliminate the mistakes and sloppy play, to be what they have been over the past three months -- one of the best teams in the NHL.
"You know they're going to come out hard and they pressured us," Marchand said. "Maybe we weren't ready for that kind of pressure, but they were just better than we were. They played their game better than we played our game. You can't do that come playoffs and expect to win."