The Bruins did not play their best game of the season on Saturday, not by a long shot. But just enough opportunism in the offensive zone, defensive tenacity in their own zone and some very good goaltending by Jeremy Swayman (29 saves) led them to a 4-1 victory over the New Jersey Devils at the Garden.

After a shaky second period, the B’s had taken a 2-1 lead into the third on goals from Fraser Minten and Morgan Geekie. They had a chance to make it 3-1 when they got their first power play midway through the period but, on their best opportunity on the 5-on-4, Alex Steeves hit the near post.

With just under 5:00 left in the third, Swayman was forced to make a great skate save on a Connor Brown backdoor play.

And with 3:35 left in regulation, the B’s finally got their insurance goal on a beautiful play, capped off by Casey Mittelstadt’s sixth of the season. Viktor Arvidsson broke the puck out of his zone on a 3-on-2 and fed Pavel Zacha just below the right circle. Zacha sent a perfect pass to Mittelstadt, who beat a helpless Jake Allen.

Andrew Peeke then sealed it with an empty netter from his own zone with 2:14 remaining, his first goal of the season.

It was Boston’s second straight win, the first time it has done that since Nov. 8 and 11.

Both teams were playing without their injured marquee players, the B’s without David Pastrnak and Charlie McAvoy, and the Devils without Jack Hughes.

New Jersey was struggling a little more with its loss, coming into the game having lost its previous four, including a 3-0 shutout loss to Vegas on Friday. As such, it was the more urgent team in the opening 20 minutes. The Devils were the better team in the first period, holding a 12-5 shot advantage. They did a good job of turning away most Bruin zone entries without much of a threat.

That appeared to be what was happening when a push by the B’s third line was scuttled by the Devils again late in the period. But just as Simon Nemec was about to gather the puck along the right boards to start the rush, Mark Kastelic picked his pocket. Kastelic found Fraser Minten in the slot and the rookie beat goalie Jake Allen for his fourth goal of the year at 17:40.

But they lost the lead just 59 seconds later.

Nico Hischier beat Zacha on a faceoff in the B’s zone to gain Jersey control. The puck eventually made its way to Luke Hughes, whose shot was deflected by Hischier. The deflection wasn’t on net, Jeremy Swayman had to play the original shot and was in no position to stop Timo Meier, who swept the puck into the wide open net from the right side of the crease.

The B’s came out much stronger in the second and regained the lead 1:12 in. Again, it came off an offensive zone steal.

After a team went just wide, Jersey gained control of the puck behind the net. But Elias Lindholm made a steal of Brenden Dillon’s breakout pass attempt in the left circle and fed Morgan Geekie at the bottom of the left circle for a one-timer and his 22nd goal of the year.

But with the long change in the second period, Jersey started to tilt the ice in its favor again. They hemmed the B’s in their zone several times. The B’s survived, barely. Dougie Hamilton came close to tying it when a gassed Bruin team was caught on once side of the ice and he was allowed to carry the puck deep down the right wing but he clanged the crossbar.

On once such shift, a tuckered-out Nikita Zadorov finally had to crosscheck Hischier, taking the first penalty of the game.

The B’s were able to kill that off and that seemed to settle them down a bit. Zadorov, in fact, nearly gave the B’s a two-goal lead but his in-tight chip shot hit the crossbar off another great feed from Elias Lindholm.

But the Devils pushed back again by the end of the period and the B’s had to hang on just to get it to the second intermission with their very slim one-goal lead.

The Devils held a 21-9 shots on goal edge and 51-28 attempts lead through two periods.