Martinez scored his first career playoff goal early in the second period on a goalmouth scramble that Brodeur felt should have been whistled dead, and Kopitar followed about 10 minutes later with his third goal in four games off an impressive pass from Brown.
New Jersey largely controlled play before Martinez scored the game's first goal on a scramble in front of Brodeur, and the Devils repeatedly dominated puck possession. The Devils couldn't beat Quick, who might have nosed ahead in the derby for the Conn Smythe Trophy as the playoff MVP with another shutout.
The Devils again dominated the puck early in the second period, keeping it in Los Angeles' end for long stretches, but Quick made saves with everything from his blocker to his shoulder.
The Kings went ahead when Dwight King created a scoring chance with a big hit, eventually hacking at the puck underneath Brodeur's pad in front. Martinez joined the effort with Trevor Lewis and got credit for the goal when the puck finally trickled in, scoring his first goal in his 23rd career playoff game.
"I had the puck, I covered it with my stick, and the guy just pushed me," Brodeur said. "I think the referee was in the wrong position, so I guess it was tough for him to make the call."
Late in the period, Kopitar extended the lead on a stellar rush by the Kings' top line. Williams moved the puck into the zone and found Brown, who feathered a cross-ice pass to Kopitar for the Slovenian star's eighth goal of the postseason, giving Los Angeles its first two-goal lead since Game 2 of the Western Conference finals.
The Kings finally got their first power play early in the third period, and Carter found Brodeur's top shelf with a pass from Richards. Williams then caught the Devils' penalty-killers napping, and the celebration was on.
Staples Center was packed to the rafters well before Wayne Gretzky took the ice for the ceremonial opening faceoff. Los Angeles' long-suffering hockey fans hadn't seen a Stanley Cup finals game since Gretzky got them there in 1993, enduring two trips to the finals by the rival Anaheim Ducks in the previous decade while the Kings moved into their 44th season of play without a championship.
The Kings got another boost from the return of left wing Simon Gagne, who hadn't played since Dec. 26 while recovering from a concussion. Gagne is a seven-time 20-goal scorer in his first season in Los Angeles, carrying ample playoff experience from his decade with the Philadelphia Flyers, including a trip to the 2010 Stanley Cup finals.
NOTES: The 1942 Toronto Maple Leafs are the only team to rally from an 0-3 deficit to win the Stanley Cup finals. The other 24 teams facing the deficit have lost the Cup. ... The crowd of 18,764 was the largest in Staples Center history for a Kings game. Hundreds of fans in black jerseys gathered in the plaza outside several hours before game time, chanting slogans and carrying inflatable Cup replicas. ... Gagne played just over 6 minutes on 10 shifts. ... Lakers forward Pau Gasol, David Boreanaz, LL Cool J, David Beckham and Penguins star Sidney Crosby attended the game.
PHT: The Penguins' win in Game 4 shoved the Senators to the brink of elimination, but Ottawa has vowed to bring a better effort tonight (Coverage at 6:30 p.m. ET; Live Extra, NBCSN).
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