Viktor Kozlov put the Islanders in first place with the first four-goal game of his NHL career.
Kozlov's scoring spree offset Brendan Shanahan's 18th hat trick and helped the Islanders take the Atlantic Division lead with a victory over the Rangers on Sunday night.
"This is the first time I ever had four goals in any game, maybe except junior," Kozlov said. "It's not only me, but it's my linemates and my team."
Kozlov's wrist shot from the slot beat Kevin Weekes to the glove side with 6:08 left and he completed the scoring on another wrist shot with 1:36 left.
With their fifth victory in seven games, the Islanders pushed their points total to 31, one more than the Rangers and Devils.
"It'll definitely make the bus ride back to Long Island a bit happier," goalie Rick DiPietro said, "but it's not like we've clinched the division. There's still a lot of hockey left."
Miroslav Satan and Chris Simon each had a goal and assist for the Islanders, and Arron Asham also scored. DiPietro made 39 saves.
Jaromir Jagr had the other goal for the Rangers in their first outright loss in seven games (3-1-3). Henrik Lundqvist started and stopped four of eight first-period shots. Weekes made 10 saves in the final two periods.
Just 12 seconds after killing off a penalty, the Islanders opened the scoring when Mike Sillinger fed Satan on the right wing. Satan moved to the lower right circle and wristed a shot high to Lundqvist's short side.
Satan, who led the Islanders with 35 goals last season, was off to a slow start, but has five of his seven goals in the past nine games.
The Islanders cashed in on their first power-play chance for a 2-0 lead. Point men Radek Martinek and Satan were playing catch when Martinek found Simon down low. His turnaround wrist shot banked in off the left post.
Kozlov put the Islanders up by three with 3:32 left on a backhander from the lower left circle. Asham stepped out of the penalty box and scored on a wrist shot from the right circle with 33.4 seconds left in the period.
BLUES: Goalie Curtis Sanford will be sidelined six to eight weeks with a pulled groin, the team said. Jason Bacashihua was recalled from Peoria, Ill., of the AHL.
OILERS: Forward Ryan Smyth is out indefinitely with a broken right thumb, sidelining a player who has 16 goals in 24 games. He was hurt during the first period of a 4-0 loss to Columbus on Saturday night.