The Canadiens won their fourth straight, the longest current winning streak in the NHL. They have not won this many consecutive games since capturing six straight last March.
Montreal goaltender Carey Price started every game this season prior to Friday and has compiled a 6-2-1 record, but Alex Auld gave Price his first rest of the year and came through with 32 saves.
Tomas Plekanec opened the scoring with a power-play goal 2:42 into the first period, his fifth of the season.
Matt Martin produced the only goal against Auld with 3:15 left in the second and Pouliot put Montreal back in front with a wrist shot. Travis Moen gave the Canadiens insurance with 1:49 remaining in regulation by tipping in a shot from Brian Gionta.
Dwayne Roloson allowed all three goals on 26 shots.
Montreal won for the 12th time in its last 15 meetings with the Islanders.
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