The Islanders were five minutes and change away from the sort of grind-it-out win that could have left them feeling primed for the second half of the season.
But it's hard to grind anything out against the Rangers and Rick Nash. Nash's neat deflection of Derek Stepan's shot tied the score at 1 with 5:23 to play before the Rangers got the break they needed with a quick power play in overtime.
Marian Gaborik delivered the power-play winner at 42 seconds of OT, giving the Rangers a 2-1 victory at sold-out Nassau Coliseum.
It was the Rangers' fourth victory in a row, solidifying their hold on a top-eight Eastern Conference spot, and left the Islanders as dejected as they've been all season.
"I thought we were playing well and we just needed to keep playing our game," Rangers coach John Tortorella said of his team's push for the tying goal.
He rode two lines for much of the third period and rode Nash in particular until he broke through, not with one of his bull rushes to the net but by flying through a shooting lane to tip Stepan's point shot down and past Evgeni Nabokov, who made 35 saves and otherwise stood out.
"The third period has been his period," Tortorella said of Nash, who has scored all eight of his goals this season in the third. "He has a mind-set that he accepts the responsibility. He doesn't say [anything], just goes out and plays."
The Islanders were livid after Michael Grabner was whistled for hooking down Michael Del Zotto as the Rangers defenseman drove to the net 21 seconds into overtime, perhaps not so much for that call but for the fact that a hard-hitting, hard-fought game brought the Islanders no power plays.
"Maybe we're wrong, maybe they played a real clean game," Matt Martin said. "We're in one of the toughest divisions in the league, and they're pretty far from a soft team. It's very frustrating."
"It's probably the toughest one this year," said Nabokov, who stoned Nash's other six shots and had one of his stronger games this season. "We had the game in our hands. That's exactly how the playoffs are. It was a great atmosphere; I wish we could have that atmosphere every night here."
The Islanders attempted to make Grabner's first-period goal stand up and tried to win for the first time this season (0-10-0) when scoring fewer than three goals.
Despite being outshot, the Islanders were able to control the front of their own net and generate chances off the counterattack. Martin had a shorthanded breakaway late in the second that Henrik Lundqvist (27 saves) denied and Matt Moulson and Grabner each had break-in chances that missed.
"We get one of those and it's 2-0, it's a different game," Jack Capuano said. "I feel bad for the guys. They deserved a couple power plays, but [the Rangers] got the break in OT and they took advantage."
"We've just got to try and put this one behind us, tough as it is," said John Tavares, who was held off the scoresheet. "We have to keep building off what we've done the past few games."
The Islanders finish their seven-game homestand Saturday against the Caps with another chance to reach .500. The Rangers return to the Garden Friday night to face the Senators with a chance to keep climbing up the East ladder. They are six points back of the Atlantic Division-leading Penguins with two games in hand.