Kings’ defense and season are teetering after 6-3 loss to Sharks in Game 4

The identity the Kings had sweated and strained to build over six grueling months was shattered this week in two playoff losses to the San Jose Sharks, defeats that left the Kings at the brink of elimination and shoved them backward in their apparently never-ending rebuilding process.

Unable to stifle the Sharks’ potent offense for the second straight game, the Kings gave up three goals on four shots in the third period and fell, 6-3, before a sellout crowd at what might be their last game at Staples Center this season.

“To me, the playoffs are pretty simple,” Kings defenseman Rob Scuderi said. “It’s black and white. You either get the job done or you don’t, and I think everybody knows which side which team is on.”

After yielding only three goals in splitting the first two games of their first-round series, the Kings gave up 12 goals on 63 shots in losing Games 3 and 4. The Sharks’ depth has beaten back the demons they collected while fizzling in the playoffs so often. They’ve made adjustments the Kings can’t counter and have earned their 3-1 series lead and chance to close it out Saturday at HP Pavilion.

“We’re going back home, it would be nice to wrap it up,” said brawny winger Ryane Clowe, who scored twice and has four goals in the series.

Should the Kings win, a sixth game would be played Monday at Staples Center. But their home-ice advantage was nonexistent in these two games, two of their worst efforts.

“We’ve allowed 12 goals at home and we pride ourselves on being a real good defensive team,” Kings right wing Justin Williams said. “The math certainly doesn’t add up.”

It adds up to the 11th time in their history they’ve faced a 3-1 series deficit. They’ve overcome that only once, in the 1989 Smythe Division semifinals against Edmonton.

“There’s no doubt that we’ve unwound a little bit,” Scuderi said, “and it’s something that winning playoff teams cannot do and that’s why we lost.”

The Kings had vowed to bounce back from their collapse Tuesday in Game 3, in which they squandered a 4-0 lead and lost, 6-5, in overtime. They spotted San Jose three goals in the second period Thursday but cut that to 3-2 late in the second period on goals by Brad Richardson and Williams and the ever-hopeful crowd was poised for a tense third period.

But goaltender Jonathan Quick, outstanding during a five-on-three Sharks power play in the first period, was abandoned and left to his own increasingly ineffective devices as the game wore on. Joe Thornton -- who celebrated by blowing two kisses to Sharks fans in the stands -- and Joe Pavelski scored in the first 3 minutes 22 seconds of the final period to break the game open and increase the Sharks’ growing confidence level.

The Kings closed their locker room for several minutes after the game and were searching for ways to end this ugly meltdown.

“Try to keep them from scoring six goals a game,” was defenseman Jack Johnson’s suggestion. “They’ve scored 12 goals in two games. That’s embarrassing.”

Clowe began the barrage at 3:58 of the second period, when his shot deflected off Johnson’s skate and off the stick of Kings defenseman Alec Martinez and into the net. The rattled Kings allowed defenseman Jason Demers to convert a fine pass from Logan Couture at 5:12, and Clowe’s power-play rebounder at 9:28 made it 3-0.

After Coach Terry Murray called a timeout, the Kings came back on goals by Richardson, by the right post, and Williams, who benefitted when his pass to Ryan Smyth deflected off Sharks defenseman Marc-Edouard Vlasic.

But then Thornton, off a swift passout from Patrick Marleau at 2:28, and Pavelski, who deflected a Dan Boyle shot at 3:22, began putting the game out of reach. San Jose’s Torrey Mitchell and the Kings’ Alexei Ponikarovsky completed the scoring as tempers flared and the Kings became frustrated.

It isn’t over yet, but the end is in sight. Again. As ever.

helene.elliott@latimes.com

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