Kings try to regroup after shocking collapse in Game 3

It was like a dream where something awful is happening but you’re powerless to stop it — except the Kings were wide awake for their public undressing Tuesday at Staples Center.

Boosted by a raucous crowd they had taken a 3-0 lead over the San Jose Sharks in the first period and appeared poised to take control of the teams’ first-round playoff series. Their rout seemed assured when Sharks goaltender Antti Niemi lost his stick and was helpless to prevent Brad Richardson’s unassisted goal 44 seconds into the second period.

What could go wrong?

Everything.

The Kings unraveled while San Jose shortened its bench to three lines and defied its reputation as mentally fragile in postseason play. The Sharks scored five times in the second period and earned a 6-5 victory and 2-1 series lead when Devin Setoguchi, the trailer on a three-on-two, scored from the slot 3 minutes and 9 seconds into overtime.

“We embarrassed ourselves. We played a terrible game,” Kings Coach Terry Murray said. “Now what you have to do is, how do you deal with that kind of performance?”

Murray dealt with it by reviewing video with coaches and players but not changing the lineup for Game 4 Thursday at Staples Center. Despite another desultory effort, Dustin Penner will keep his spot and enforcer Kevin Westgarth will stay on the fourth line. Speedy Oscar Moller, unable to grow to 6 feet 2 by Thursday, will be scratched again.

Players put on happy faces at practice Wednesday. “There’s no reason not to be upbeat,” goaltender Jonathan Quick said. “We’re not down, 3-0. It’s a 2-1 series. We’re right there.”

It looked like it would be 2-1 in their favor. They controlled the tempo early on, killed their first penalty and chased Niemi.

Then, inexplicably, they began to sit back and stopped getting the puck in deep. Patrick Marleau got a tap-in at 3:08. Penner took a roughing penalty away from the play and Ryane Clowe threw the puck on net and got a fortunate deflection off Willie Mitchell’s stick. The Sharks had new life, new energy.

“And you know the push is going to come,” Murray said. “They’ve changed the goaltender, they’ve called time out. They’ve had their meetings in between periods. You know the coach is upset. Players are fired up.

“Now it’s a matter of, ‘Let’s get after them and see what they can handle’ kind of an attitude, and they kept coming in waves.”

Impressive rookie Logan Couture made it 4-3 on a one-timer at 13:32 while the teams were skating four on four.

“You want to stay composed and stay calm,” Kings center Jarret Stoll said. “You don’t want to start panicking on the bench. You panic on the bench you’re going to be panicking out there and we definitely were panicking out there and not being composed and making plays. We basically stopped playing.”

They were spending too much time in their end, “and when you do that bad things are going to eventually happen and they keep coming and keep coming,” Stoll said.

He thought they had stopped the bleeding when he set up Ryan Smyth for a backdoor goal and a 5-3 lead at 13:47. “I remember talking on the bench with the guys and saying, ‘Let’s have a good four minutes here, get in the dressing room and we can regroup. Play a hard four minutes,’ ” Stoll said. “But they ended up tying the game in those four minutes. It was just a nightmare second.”

As the Kings scrambled in their own zone, Clowe took a pass from Dan Boyle and was alone by the left post for a redirection at 18:35. Joe Pavelski brought the Sharks even with shot from the slot at 19:29.

San Jose went end-to-end to win it, from defenseman Niclas Wallin to forward Patrick Marleau on the left wing to Setoguchi on the right. The Sharks became only the fourth team to overcome a playoff deficit of four goals. The Kings became numb.

“I think we learned our lesson. I’d like to believe we have,” Mitchell said.

Defenseman Drew Doughty vowed, “It’s never going to happen again,” and maybe it won’t. But this was a kick in their remaining teeth. We’ll see Thursday if they have any bite left.

helene.elliott@latimes.com

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