NHL

‘KING’ KILLERS

Take it from Billy Guerin, who began his career on the other side of the Hudson and now is captain of the team on the other side of the East River.

Take it from Guerin, who understands exactly what it means for the Islanders – or, way back when, the Devils – to beat the Rangers.

“Hey, it’s David against Goliath,” Guerin said after his Islanders trained their slingshots on Henrik Lundqvist to score three times within a third-period span of 10:04 to defeat the Rangers 3-2 last night at the Coliseum.

“We’re trying to establish ourselves here as a team, that’s the primary objective, but beating the Rangers is always going to be very sweet, just the way it was when I was in New Jersey.”

If it was a sweet night for the Islanders, 2-0 against the Blueshirts this season and 7-1-2 over the last two years, it was a sour one for the Rangers, who were unable to hold a 1-0 lead after two periods and a 2-1 lead they carried midway into the third.

In a flash, it all disappeared for the Rangers and Lundqvist-their 159:34 shutout streak and their four-game winning streak.

What did not disappear, however, was the zero under the win column on the road for the Blueshirts, who at 0-5-1 away from the Garden are the only team in the NHL other than the woebegone 0-7 Lightning without a victory in their white uniform systems.

Ah, systems – as in the repeated deviations from their system that cost them the game. The Rangers turned over the puck a monstrous number of times, leaving themselves vulnerable to repeated attacks.

“We didn’t play smart enough, and that includes me,” said Sean Avery, whose defensive-zone turnover on the boards led to Miro Satan’s game-winner at 11:12, just under two minutes after Ruslan Fedotenko had tied it.

“I have to get that puck out, there’s no question about that. A game we’re winning 2-1 in the third period? Of course we should win that game.”

Maybe, but for how long do the Rangers realistically expect to survive scoring twice a game? Last night marked the fourth straight time the Rangers were limited to two goals, and the 11th time in 15 games overall they’ve been held to two or fewer.

To that extent, what exactly is going on with Scott Gomez? If Jaromir Jagr has elevated his game after the breakup of his brief partnership with No. 19, Gomez is flat-lining. Yes, he did have an assist on Paul Mara’s third-period power-play goal, but he was beaten badly on the Islanders’ first goal. Gomez seems to have left his confidence and playmaking ability somewhere in the Lincoln Tunnel.

The Rangers have won as a team, and last night they lost as a team. Lundqvist said that even with a 1-0 lead after two, “We said between periods there was no way we were going to win if we kept playing the way we were; we just gave the puck away too many times.”

They gave the puck away and they gave the game away. Well, not quite, for Rick DiPietro and the Islanders took it after taking it to the Rangers.

And so, when Guerin was asked whether the Islanders are the best team in New York, the captain paused, visualizing the bulletin board material his answer might become.

“We’re one of them,” he said.

So they are.

Isles 3 Rangers 2

larry.brooks@nypost.com