A win over the basement-dwelling San Jose Sharks would not have meant a whole lot to the Bruins a week ago. But after three straight ugly losses in which the B’s allowed 17 goals, any positive development was welcome.

Though the B’s started a tad slowly, they nailed down a 3-0 win over the Sharks on Thursday at the Garden, with a couple of encouraging style points to boot. They got goals from both of their rejiggered top six lines, the pushed back emphatically when challenged physically and Jeremy Swayman, pulled in his last start through little fault of his own, posted his second shutout of the season.

The B’s had a long way to go to get their game back to respectability, but it was a good first step.

The two teams played a low-event, scoreless first period which, for the Bruins in the early going, didn’t look unlike some of the hockey they’d been playing on their three-game losing streak. In the offensive zone, they seemed a bit brain-locked, waiting a hair too long to make a play, the Sharks were able to get their sticks in the way. The B’s did, however, start to feel it towards the end of the period.

On the flipside, the B’s didn’t really give up too much defensively. They held a 10-9 shot advantage and the sharks didn’t have any real Grade A chances.

The momentum the B’s slowly built toward the end of the first led to the first goal of the game early in the second period as well as the B’s first lead in a game since beating Florida over a week ago.

Matt Poitras made a nice play to glove down a clear attempt at the right circle and then fought off two Sharks to make a nifty backhand pass to Danton Heinen, who ripped his third of the year past Mackenzie Blackwood at 1:39.

Slowly but surely, the B’s started to get some of their creativity back. On a 4-on-4, Poitras was stopped on a 2-on-1, but they would push the lead to 2-0 at 8:10. David Pastrnak made a short pass at the San Jose blue line to Pavel Zacha and Zacha dished a backhand feed to Jake DeBrusk for a short breakaway. DeBrusk made the most of it, throwing a a nice move at Blackwood before slipping it through the goalie’s pads for the two-goal lead.

But things got nasty in the second half of the period, and it didn’t help the B’s much, though they showed plenty of fight. On a delayed Sharks penalty, Givani Smith rammed Brad Marchand from behind into the boards on a dangerous play and only got a two-minute minor for boarding, despite coach Jim Montgomery lobbying for a five-minute major. In the immediate aftermath of the hit, Heinen went after Smith before Derek Forbort came in over the top.

The B’s couldn’t cash in on the power-play and then things went haywire in the final minute of the period. Trent Frederic dropped the gloves with Smith for the Shark’s previous transgression, took perfect left and got up off the mat to land a few of his own.

Then the B’s put themselves in big trouble. With the Sharks on the ropes, Charlie McAvoy was called for boarding while Marchand squared off with Fabian Zetterlund. Marchand, however, got the extra two for roughing on top of the five-minute major and the B’s would start the third period with 1:35 of 5-on-3 time.

And they rewarded themselves for the aggression they showed, killing it without giving up a shot on net with some tremendous work from Brandon Carlo, Derek Forbort, Charlie Coyle and Zacha.

When the B’s got their next power-play opportunity, they made the Sharks pay at 6:37. Zacha dished it to David Pastrnak with a cross-ice pass in the neutral zone and stayed parallel with Pastrnak as the sniper made a nice shimmy move to gain the blue line. He sifted a pass back to Zacha in the middle of the ice and Zacha notched his eighth of the year on a backhander.