Then in overtime, Canucks defenseman Kevin Bieksa lost control of the puck behind his own net and Slava Voynov tapped it out front to a wide-open Kopitar, who put it past a startled Roberto Luongo for the game-winner.
Kyle Clifford also scored and Ben Scrivens made 37 saves for the Kings, who had lost each of their previous two games in overtime.
Chris Tanev and Henrik Sedin scored for slumping Vancouver, which fell for the seventh time in eight games.
Luongo finished with 19 stops.
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