So much for all the hype about a showdown.

With three goals in a dominant second period, the Metropolitan Division-leading Islanders decked the Rangers for the second time this season at Madison Square Garden Tuesday night and extended their lead over the Blueshirts to seven points with a 3-0 win.

It was the first time that the Islanders blanked the Rangers at the Garden since Billy Smith did so on Dec. 17, 1975, also 3-0.

Flat at home after winning three straight in California and 13 of the last 14 games, the Blueshirts were outplayed by the energized Islanders, who unleashed 32 shots at Henrik Lundqvist in the first 40 minutes, including 19 in the decisive second period, and 44 overall.

"We got outskated, outbattled in our zone," said Rangers captain Ryan McDonagh. "We haven't given up that many shots in a long time. We were the slower team tonight, which we haven't been in this stretch."

The Rangers, who couldn't solve the Isles 1-3-1 defensive alignment, had just 27 shots on Jaroslav Halak, who posted his fourth shutout and 23rd win.

"They definitely deserved to win," said Lundqvist, whose arm didn't fully block a shorthanded shot from the right circle off the rush by Frans Nielsen with 41 seconds left in the second for the 3-0 lead. He was replaced by Cam Talbot to start the third. "I thought I had it; I felt really good, made a lot of good saves, but when you do face that many scoring chances, some bad things are going to happen."

The Islanders forced those bad things. "What really put us in a tough spot was the turnovers," Lundqvist said.

The Blueshirts played most of the game without center Derek Stepan, who sustained an upper-body injury, apparently a hand issue, and played just 2:22 of the second before leaving.

In the third, the Islanders (29-13-1, 59 points, and a season-high 16 games over .500) protected the lead.

It was only the second time that the Rangers, who had been averaging 3.13 goals per game, have been blanked this season; the other was a 1-0 shootout loss to Winnipeg on Nov. 1.

"We couldn't get out of our own end," Rick Nash said. "When we did, we couldn't get it deep. We fed right into their game plan."

The Rangers, who had scored first in eight of their last nine games, came the closest to scoring in the first. On a drive to the net, Nash hit the post at 16:32. On the rebound, Derick Brassard's shot went behind Halak and hit the same post. At 11:20, Mats Zuccarello's shot from the left side had dinged the far post.

"In the first period, the game could've totally changed," Islanders coach Jack Capuano said. "That's the way the puck bounces sometimes."

In the second, the Islanders peppered Lundqvist. After a pad save on a wrapround by Brock Nelson and a follow by Nick Leddy, coach Alain Vigneault called a timeout at 3:22. It didn't help.

With Lundqvist sprawling, Cal Clutterback scored, but the goal was immediately waved off because Casey Cizikas had bumped Lundqvist.

Anders Lee cracked the seal on a rebound at 9:49, after Calvin DeHaan's shot.

After the Rangers killed an interference penalty on Marc Staal, Nikolay Kulemin stopped Kevin Klein's clear in the slot and quickly released a shot to the high corner at 16:31, his eighth of the year, for a 2-0 advantage.

Lundqvist stopped Cizikas on a right side breakaway, but with Travis Hamonic off for crosschecking Dom Moore, the Rangers had their first power play at 18:48. It backfired when Nielsen scored.

"No question we were a step behind in our execution, a step behind in our decision-making," Vigneault said. "We gave up that shorthanded goal and that seemed to take the energy right out of our game."