Islanders defenseman Noah Dobson celebrates his goal with teammates Anders...

Islanders defenseman Noah Dobson celebrates his goal with teammates Anders Lee, Brock Nelson and Alexander Romanov during second-period NHL game action against the Senators in Ottawa, Ontario, on Monday. Credit: The Canadian Press via AP/Patrick Doyle

OTTAWA — Rallying from two-goal deficits in the third period on back-to-back nights last week served as early-season signature moments for the Islanders.

Coach Lane Lambert thought this latest victory topped those.

“It was really a character win,” he said. “It was as much a character win — or more — than the comebacks because we fought through a lot of adversity.”

Special teams made all the difference for the Islanders as they opened a four-game road trip with a tense 4-2 win over the Senators on Monday at Canadian Tire Centre.

The Islanders (11-6-0), who won their second straight and for the ninth time in 11 games, went 2-for-3 on the power play and killed off five of the Senators’ six man-advantage opportunities. They yielded only a five-on-three goal despite the Senators taking 11 power-play shots.

“They have a good power play but we were well-prepared,” said Ottawa native and former Senator Jean-Gabriel Pageau, who scored the winner as he got to the crease for a power-play goal at 8:21 of the third period to make it 3-1. “I thought the guys battled hard. A lot of sacrifice. A lot of blocked shots [20]. Varly in net was outstanding. He made some amazing saves for us.”

Semyon Varlamov made 36 saves, facing 28 shots in the last two periods. Cam Talbot stopped 31 shots for the Senators (5-9-1), who had snapped an 0-6-1 skid with Saturday’s 4-1 road win over the Flyers.

Claude Giroux pulled the Senators within 3-2 at 13:08 of the third period as he beat Anthony Beauvillier to the crease, but Brock Nelson clinched it with an empty-netter with 1:10 remaining.

“Special teams is a factor in a lot of games,” said Noah Dobson, who quarterbacks the first power-play unit and regained a 2-1 lead for the Islanders with an unassisted shot through traffic at 13:15 of the second period with the teams skating five-on-five. “We’ve had a lot of looks over the last couple games on the power play that didn’t go in. We got rewarded with a couple tonight, which was huge. The kill was great. A big win for us.”

The Islanders had rallied for a 4-3 overtime win over the visiting Flames on Nov. 7 and followed that with a 4-3 comeback win over the Rangers at Madison Square Garden the next night.

The Islanders played shorthanded for more than nine minutes in the second period against the Senators yet still led entering the third.

Ross Johnston, inserted on the third line with Josh Bailey not in the lineup, took a roughing call against Franklin Square’s Shane Pinto in front of the Senators’ bench at 7:11. Defenseman Scott Mayfield then caught Brady Tkachuk with a high stick in front of the Islanders’ crease, drawing a four-minute double minor and giving the Senators a five-on-three advantage for 34 seconds.

It took only 11 seconds of the two-man advantage for Drake Batherson to blast one past Varlamov from low in the left circle off Tim Stutzle’s feed.

The Islanders killed off the remaining 3:49 of Mayfield’s penalty. Still, it marked the eighth time in nine games that they have allowed a power-play goal after starting the season 28-for-28.

Oliver Wahlstrom, inserted on the second power-play unit with Bailey absent, rifled a shot past Talbot (31 saves) from the right circle on the man advantage to give the Islanders a 1-0 lead at 11:53 of the first.

“With me, I feel it takes one sometimes,” said Wahlstrom, who snapped an eight-game goal drought. “Those are exciting to get for a goal-scorer. You can just set your feet and let it rip.”

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