It was the sixth road win in a row for the Islanders, who forced overtime when Brock Nelson's goal early in the third period evened the score.
"We've been a decent road team," Islanders coach Jack Capuano said. "Simple hockey maybe, and doing the right things. Goaltending has been pretty good for us. Our special teams on the road over the last two weeks has been good."
Brian Strait helped set up the winner with a pass to Grabner in the Avalanche zone. Grabner skated across the slot, appearing momentarily to lose control of the puck, before getting hold of it with his stick and circling back to unleash the shot from between the circles. He got enough on it to get it past Semyon Varlamov.
"The puck bounced a little bit," Grabner said. "I don't know if my stick got caught on the boards or the ref there, I almost lost it and couldn't control the puck, but I got it back in the corner. The guys opened up some room by driving to the net and I got a chance to shoot from the hash marks."
Kevin Poulin, who had 30 saves, won his fourth straight decision and improved to 5-1 in his last six games. He credited the recent road success to the team's increasing rapport with one another.
"Earlier in the season, we didn't have the groove on the road," Poulin said. "As the season goes on, you create chemistry. I thought we've played really well defensively the last three or four games."
Despite the loss, the Avalanche finished their season-high seven-game homestand with a 4-1-2 record for the second-best points percentage (.714) during a homestand of at least seven games in franchise history. The Avalanche finished a nine-game homestand 6-2-1 (.722) from Feb. 9-March 9, 2002.
"You wanted to pick up as many points as possible and I think 10 out of 14 is pretty good," Avalanche coach Patrick Roy said. "It was a hard-fought game. Unfortunately, we were on the wrong side of the game but I thought we did a lot of good things out there. We battled and defensively we played well. We didn't give them too many chances."
Nathan MacKinnon, who leads all NHL rookies in points, broke a scoreless tie at 18:15 of the second period. He gathered in an outlet pass from Andre Benoit just past the red line and dashed down center ice, blowing past defenseman Matt Donovan in a stunning show of speed before lifting a wrist shot over the left leg of Poulin as the goalie lay sprawled in front of the net.
It was the 15th goal of the season for MacKinnon, who has 29 points in 44 games.
The Islanders evened the score 4 1/2 minutes into the third, when Nelson got off a shot in the slot that got past Varlamov. It was Nelson's fifth goal of the season.
The Avalanche and Islanders met for the first time since Nov. 10, 2011, when Colorado won 4-3 in overtime. ... The Islanders are 16-4-2 when they score at least three goals and 1-18-5 when they're below that threshold. ... Frans Nielsen played in his team-leading 175th consecutive game for the Islanders. ... The Avalanche head to Minnesota to play the second game of a back-to-back set on Saturday. It is the fifth of 10 back-to-back sets for the Avalanche this season. ... Jamie McGinn of the Avalanche scored his 100th career point with an assist on MacKinnon's goal.
Copyright by STATS LLC and The Associated Press
DENVER, CO - JANUARY 10: Matt Duchene #9 of the Colorado Avalanche warms up prior to facing the New York...