Sharp's goal 1:34 into overtime Thursday gave the Blackhawks a 3-2 victory over the New York Islanders, and he struck again Sunday, outbattling Brett Burns for a rebound and finding the San Jose net with 34 seconds left in the extra frame.
The game-winner capped a Chicago comeback in which the Hawks netted the 2-2 equalizer with 1:06 left in regulation.
Ray Emery stopped 35-of-37 shots to earn the win.
Niemi finished with 31 stops.
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