Niemi notched his second shutout of the season and the ninth of his career, surviving three Kings power plays en route to the victory.
Setoguchi's goal came on a long wrist shot from the slot that fooled Kings goalie Jonathan Quick with 1:06 left in the second period, and the Sharks went to on avenge a 4-0 loss at the hands of Los Angeles on Monday.
Quick ended up making 18 saves in absorbing the hard-luck loss, the third straight for the Kings, which saw San Jose leap-frog them into second place in the Pacific Division.
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