With the Sharks up 3-2, Ryane Clowe broke in on goal down the left side and found Couture free across the ice. He fed him a perfect pass and Couture unleashed a shot past Mikka Kiprusoff for a 4-2 advantage.
Joe Thornton, Clowe and Joe Pavelski also scored for San Jose.
Mark Giordano and Jay Bouwmeester tallied for Calgary and Kiprusoff turned aside 31-of-35 shots.
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