Islanders’ third-period meltdowns becoming troubling trend

MONTREAL — Earlier this season, the Islanders were going into third periods full of swagger, even if the scoreboard said they should feel otherwise.

Now, they seem to walk into the final 20 minutes waiting for the other shoe to drop, even if the scoreboard says they’re winning.

A pair of blown leads to the Canadiens in the third period Saturday on the way to a 4-3 overtime loss was not a result that can be taken in isolation. That came after the Islanders blew a 4-2 third-period lead to Vancouver on Thursday, which comes on the heels of an entire month in which they constantly tripped over themselves in the third.

The resilience that looked like a defining feature of the Islanders over the first couple of months this season has gone, and with it, their playoff chances are starting to dwindle.

“We have to stay on the gas,” Ryan Pulock told The Post. “I think obviously throughout games, there’s highs and lows and momentum swings. When you get that goal [to take the lead] you gotta keep that momentum the best you can.”

Indeed, it looked as though the Islanders had overcome the worst of it on Saturday after Matt Martin tipped in a shot from Alexander Romanov to take the lead back just over halfway through the third period. But sure enough, the Canadiens made a push and Kirby Dach tied the score with a tip of his own with just over three minutes left.

And in overtime, Montreal went on to steal the extra point on a defensive breakdown after a power play ended, with Mike Matheson netting the winner.

“It’s hard to point your finger to one particular thing,” Noah Dobson said of the third-period issues. “Obviously it’s an area the last little bit we gotta be better on. It’s something we’re aware of.”

After Saturday, the Islanders — who at the start of the season scored stirring comeback wins over the Avalanche, Flames and Rangers — have a negative goal differential this season in third periods, having been outscored 55-54.

“There’s a certain point in time where as an individual, you have to win a battle,” coach Lane Lambert said. “And when that doesn’t happen, you decrease your chances of holding that lead.”

Sebastian Aho drew back into the lineup for Samuel Bolduc, picking up a secondary assist over 16:16.

Romanov, who assisted on Martin’s third-period goal, looked emotional as the Canadiens played a tribute video for him early in the game. Romanov was traded to the Islanders from Montreal during the draft last summer at the Bell Centre.