The loss snapped a 12-game point streak at home for Vegas, which had gone 10-0-2 at T-Mobile Arena since getting blanked by Ben Bishop and the Dallas Stars 3-0 on Nov. 28. The Western Conference-leading Golden Knights fell to 19-3-2 at home, still the best home record in the NHL.
Jordan Eberle and Ross Johnston scored for New York, which swept the regular-season series. The Islanders beat the Golden Knights 6-3 on Oct. 30 at Barclays Center.
Erik Haula scored his 17th goal of the season and Marc-Andre Fleury stopped 23 shots for Vegas (32-12-4), which was denied a chance at tying the NHL record for most wins by a team in its inaugural season (33) set by both the Florida Panthers and Anaheim Mighty Ducks in 1993-94.
Halak entered the contest with a 3.23 goals-against average and had allowed at least three goals in nine of his previous 10 games.
Johnston, called up from AHL Bridgeport on Friday and playing in just his fourth NHL game, scored his first career goal midway through the second period when his crossing pass for Cal Clutterbuck was deflected by Vegas center Cody Eakin through Fleury's pads to give the Islanders a 1-0 lead.
Eberle made it 2-0 at the 8:21 mark of the third period with a wrist shot off a pass from Mathew Barzal, who started the play with a steal from defenseman Colin Miller.
Haula finally got Vegas on the scoreboard with 5:07 to go when he redirected a shot from the point by David Perron for his 17th goal of the season.
The Islanders improved to 18-0-0 when they are leading after two periods.
--Field Level Media
NY Islanders | Vegas | |
Jordan Eberle 1 | Points | Erik Haula 1 |
Jordan Eberle 1 | Goals | Erik Haula 1 |
Mathew Barzal 1 | Assists | Colin Miller 1 |
N/A | Power Play Goals | Erik Haula 1 |
N/A | Short Handed Goals | N/A |
Jaroslav Halak .974 | Save Percentage | Marc-Andre Fleury .920 |
Jaroslav Halak 38 | Saves | Marc-Andre Fleury 23 |
Team | Shots | Goals | Power Play | Penalty Kill | Penalty Mins | Face Offs Won |
NY Islanders | 25 | 2 | 0-1 | 1-2 | 4 | 30 |
Vegas | 39 | 1 | 1-2 | 1-1 | 2 | 31 |