LOS ANGELES >> Justin Williams usually saves his greatest postseason heroics for seventh games, not openers.

And for all of his series-saving feats over the years, the two-time NHL champion had never scored an overtime playoff goal.

When Williams got the puck on his stick with an uncontested chance to stake the Los Angeles Kings to an early lead in the Stanley Cup finals, Mr. Game 7 buried the shot and the New York Rangers.

Williams scored 4:36 into overtime after a turnover by Dan Girardi, and Los Angeles beat New York 3-2 Wednesday night in a thrilling series opener.

Kyle Clifford had a goal and an assist, and Drew Doughty made up for an early mistake by scoring the tying goal in the second period. Jonathan Quick made 25 saves as the Kings moved one victory closer to their second Stanley Cup title in three years — but only after another rally in a postseason full of comebacks.

“We certainly don’t want to make a habit out of this,” Williams said. “That is a world-class team up there with world-class offense. There could have been a lot of story lines tonight. They had a breakaway in the end of the third period that (Jonathan) Quick made a great save on. We wouldn’t be sitting here right now. A lot of things (went) awry during the game.”

Game 2 is Saturday at Staples Center.

For the fourth time in their 13 victories during this postseason, the Kings rallied from a multigoal deficit to win. After the Rangers took an early two-goal lead and the Kings erased it, Los Angeles demonstrated what the rest of the Stanley Cup finals might resemble if New York can’t respond.

The Kings crushed the Rangers into the boards, dominated the puck and controlled the third period, outshooting New York 20-3. The domination abated slightly in overtime, but Los Angeles pounced when the puck bounced over Girardi’s stick and forced his panicked pass right to Mike Richards, who fed Williams for his eighth goal of the postseason on a high shot to Henrik Lundqvist’s stick side.

“The puck is going to me, I’m trying to make a play up the middle, and it bounced on me,” Girardi said. “I kind of got down to one knee, and I’m just thinking about getting it to the wall. But the guy was there and made a smart play. You can’t give Justin Williams a shot like that. He’s pretty clutch in the playoffs.”

Lundqvist made 40 saves and nearly stole an early win for the Rangers. Benoit Pouliot scored on a breakaway and Carl Hagelin got a short-handed goal in the first period, but New York spent much of the final two periods on its heels.

“Not quite sure what happened there in the third,” Rangers coach Alain Vigneault said. “Not sure if it was them being that good, or us stopping moving the puck and skating and going north-south. They definitely took it to us in the third, and they were able to get a bounce on the winning goal and put it in the back of the net.”

The tension-filled opener was a fitting start to the finals for two teams that traversed perilous paths to the first New York-L.A. championship playoff meeting since the Yankees-Dodgers World Series in 1981.

The Kings and the Rangers played a combined 41 games in the first three rounds — just one fewer than the maximum — to emerge from the middle of the playoff pack. Los Angeles didn’t blame fatigue for its slow finals start after finishing off Chicago on Sunday.

The series is big news in the nation’s two biggest cities: Staples Center was packed for the opener with roaring Kings fans still not quite accustomed to their club’s recent success. Meanwhile, thousands of New Yorkers packed Bryant Park to watch on video boards.

Pouliot scored the first goal of the series on a breakaway, stealing the puck from Doughty and skating past a stumbling Jake Muzzin. The Rangers’ small contingent of fans roared again 2:42 later when Hagelin’s breakaway shot was kicked in by Slava Voynov, who hadn’t been able to keep up with Hagelin out of the New York zone.

Los Angeles answered late in the period when Jeff Carter passed from behind the net to Clifford, who banged in a sharp-angled shot for his first playoff goal since April 23, 2011. The grinding forward had played 37 straight postseason games without a goal.

Doughty tied it for the Kings with a beautiful move, toe-dragging around Derek Dorsett and firing a wrist shot past Lundqvist for his fourth goal in six games.

NOTES: The winner of Game 1 in the finals has claimed the Stanley Cup roughly 77 percent of the time. … The Kings hadn’t won an overtime playoff game at home since May 6, 2001. … Kings D Robyn Regehr missed his 14th straight playoff game with a knee injury. Regehr is skating in practice and feels ready to play in his second career Stanley Cup finals, but the veteran realizes the Kings might not want to change a winning lineup.