After Adam Fox hit the crossbar 1:11 into the third period, Josh Bailey extended the Islanders lead to 2-0 at 5:37. Bailey cut diagonally from the left wing through the slot before tipping Pelech's slap shot from the right circle past Halak.
"Against your rivals at home, you feel that extra boost and feels a little more like a playoff-type atmosphere," Bailey said. "It'd be a little [more] tighter checking, and that's what it felt like out there."
Palmieri made it 3-0 at 15:22. His shot from the edge of the right circle bounced in and out of the net. Play continued for a few moments before it was reviewed in the NHL Situation Room.
"It always feels good [to get back on track]," Palmieri said. "There were some things that we liked about our game over the weekend and maybe didn't get rewarded for it, but this one's obviously always a big one, especially at home. So, it felt really good to beat those guys."
The Rangers outshot the Islanders 41-29 for the game. Thirty-two of the 41 shots came at even strength. Another eight came on the power play, and they had one short-handed attempt.
"We're confident in the group we have here," Rangers captain Jacob Trouba said. "We know we can score goals. We're getting opportunities, they're just not going in. It is what it is. All we can do is keep working and eventually things are going to turn for us."
NOTES: The win was the Islanders' first against the Rangers at UBS Arena. The Rangers won both games there last season, the arena's first. … The Islanders penalty kill went 3-for-3 and is 25-for-25 this season. The seven games without allowing a power-play goal to start the season ties the 2008-09 Minnesota Wild and 2014-25 Detroit Red Wings for the most since 1977-78, when special teams began being tracked. … The Rangers called up right wing Julien Gauthier from Hartford of the American Hockey league. He played in place of Vitali Kravtsov, who Gallant said was day to day with an upper-body injury. Gauthier skated on the third line with Jimmy Vesey and Barclay Goodrow and had two shots on goal in 10:44 of ice time. … Bailey played his 999th NHL game.