Michael Grabner put the Islanders ahead in the first period last night at Nassau Veterans Memorial Coliseum in Uniondale, New York.
Rick Nash tied the game with 5 1/2 minutes remaining in the third period and Gaborik fired the winning goal 42 seconds into overtime.
The Rangers improved to 12-8-2 for 26 points, while the Islanders fell to 10-11-3 and 23 points.
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