''It feels good,'' Toffoli said. ''Obviously, scoring a goal this early makes it a little easier, but at the same time, you've just gotta keep working.''
Troy Stecher had a goal and two assists for a career-high three points, and J.T Miller had three assists. Bo Horvat, Adam Gaudette, Tanner Pearson, Loui Eriksson, Elias Pettersson and Jake Virtanen also scored for Vancouver. Jacob Markstrom made 34 saves.
Miller said there is still time for his chemistry with Toffoli to improve.
''Oh, there were a couple breakdowns,'' he said. ''He was wide open on a couple. But like we talked on Day 1, he knows to get into that shooting position. The puck's going to come to him and he's got a heckuva shot.''
David Pastrnak scored his league-leading 44th and 45th goals of the year for Boston. Chris Wagner also scored. Tuukka Rask made 21 saves before being replaced by Jaroslav Halak with 13:32 left in the third period. Halak gave up three goals on eight shots.
''The way I look at it from a goalie's perspective, it's kind of one of those `when it rains, it pours,' type of things,'' said Rask. ''When it's not bouncing, it's not. Doesn't matter if it's 2-1, or 9-3 or 15-3, it's a loss. Move on and try to keep it tight next game.''
The win moved the Canucks into second place in the Pacific Division. They're two points behind the first-place Vegas Golden Knights.
The Canucks were 1 for 3 on the power play, while Boston went 1 for 2.
The loss was the first in six games for the Bruins, who were wrapping up a four-game trip. Boston maintains a five-point edge over the Tampa Bay Lightning at the top of the NHL standings.
''Listen, you're going to have games like this, so I'm not going to lose sleep over this hockey game,'' Boston coach Bruce Cassidy said.
''I even look at our schedule and sometimes you look at it and go `Boy that's going to be a tough one' at certain parts of the season. This was one that we thought would be a tough one and now Vancouver is fighting for first place, so that's just the way it is sometimes.''
Stecher opened the scoring for Vancouver at 4:14. His fourth goal of the year was a shot from the right boards that found its way through traffic in front of Rask and into the net.
At 7:06, Pastnak broke in alone and made a crafty deke before sliding the puck around Markstrom's left skate.
Less than two minutes later, Thatcher Demko briefly stepped into the Vancouver net after Markstrom left the game for medical attention when an errant high stick threaded its way through his mask.
Demko was not required to make any saves before Markstrom returned 1:48 later, as Jeremy Lauzon was sent to the penalty box after holding Elias Pettersson.
On the ensuing power play, Horvat put the Canucks up 2-1, beating Rask high to the blocker side off a Miller pass from below the goal line.
''It was one of the stronger games I've seen Bo play,'' coach Travis Green said.
''I think his game has been trending in the right direction. He's got a lot of tough matchups but he's starting to learn the little areas of the game, just the little details from a checking standpoint that for him pay off offensively as well.''
Vancouver added to its lead in the second, when Quinn Hughes intercepted Pastrnak's clearing attempt, then evaded him along the boards before feeding Gaudette for his 11th of the year.
Emotions ran high after Pearson and Eriksson extended the Canucks' lead to 5-1 lead late in the second. First, Bruins captain Zdeno Chara tangled with Tyler Myers. Later, Canucks captain Horvat traded punches with Charlie Coyle.
In the third, Pettersson scored his 25th of the year. Pastrnak and Wagner answered for Boston before Toffoli beat Halak twice. After Virtanen rounded out the scoring with 1:45 remaining, the fans at Rogers Arena chanted ''We want 10!''
With the win, the Canucks closed out their six-game homestand with a 3-2-1 record.
NOTES: Oscar Fantenberg returned on the Vancouver blue line after missing five games with a head injury.
Bruins: Host the Calgary Flames on Tuesday.
Canucks: At Montreal Canadiens on Tuesday.
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