After the two teams battled through a scoreless regulation and overtime, the contest moved to a shootout.
He moved down the right side, faked a shot, then came around to the left of the net, firing a shot that a prone Niemi managed to stop by lifting a leg off the ice.
Niemi finished with 24-save shutout for the surging Sharks, who remained undefeated through nine games (8-0-1).
Howard turned aside 27 shots for his 17th career whitewash as Detroit dropped a second straight following four consecutive wins.
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