Lakers are uh-oh-for-five after falling apart at end of 120-106 loss to Oklahoma City

The switch was finally flipped . . . completely off.

The Lakers ran into their first five-game losing streak since 2007, foundering yet again in a 120-106 loss to Oklahoma City on Sunday night at Staples Center.

It’s a bad idea to play defense for only one quarter, the Lakers giving up 36-30-22-32 across the board and falling into a tie with Dallas for second place in the Western Conference.

Worse for them, they’re only one game ahead of Oklahoma City and could actually slip all the way to fourth in the West.

Or maybe that’s the good news for the Lakers. They actually have to prove something in their final two regular-season games.

A little more than a week ago, as the Lakers moved ever so close to San Antonio and ahead of Chicago, they faced gentle questions about a season on the rise.

Will the starters get some rest down the stretch? Are 60 victories possible? When is “Khloe & Lamar” going to debut?

On Sunday, a new question popped up. Do the Lakers have what it takes to win it all?

Not in the final three minutes Sunday, as they somehow gave up 17 points while scoring only two — a concession dunk with nine seconds left — and a Thunder fan yelled the “M-V-P” chant while Kevin Durant shot two free throws in a rapidly emptying arena.

Kobe Bryant’s three-point play actually gave the Lakers a 104-103 lead with 3:10 to play. He had three turnovers after that, and one possession summed up everything: Ron Artest airballed a three-point attempt, Bryant took the rebound and airballed his own three-point attempt.

He waited 62 minutes to talk to reporters after the game, an eternity even for an NBA player.

“I didn’t want to redecorate the walls in here, so I made the effort to just go in the training room and keep to myself,” he said.

Bryant had 31 points on 10-for-19 shooting. Pau Gasol had 26 points on 10-for-16 shooting and did his best to rebuff a “soft” label applied by Oklahoma City center Kendrick Perkins in a recent magazine interview. Gasol, however, took only four rebounds in almost 33 minutes.

Durant had 31 points and Russell Westbrook had 26 for the Thunder, who shot a breezy 55.6%.

“We’re just playing horrible defense,” Bryant said.

Now the Lakers are forced to play hard against San Antonio and Sacramento, though they hold the first playoff tiebreaker with Dallas and Oklahoma City.

Bryant also moved to within one technical foul of an automatic one-game suspension after picking up his 15th. Bryant didn’t like Perkins wrapping an arm around his neck after Bryant set a screen in the second quarter.

If Bryant gets a technical Tuesday against San Antonio, he is suspended for the regular-season finale Wednesday in Sacramento. If he behaves appropriately Tuesday but picks up a technical against the Kings, he is suspended for the season opener next season.

Perkins, the former Boston Celtics center acquired by the Thunder at the trade deadline, also irritated Andrew Bynum later in the second, pushing him a few feet in the lane after Bryant’s short running jumper. Bynum retaliated by throwing the ball with two hands at Perkins’ chest and was called for a technical foul.

The Lakers surrendered 66 points in the first half, the most they’ve given up this season, but managed to clamp down in the third quarter.

Their fourth-quarter collapse was the type that would cost them a playoff game. Maybe even a series.

mike.bresnahan@latimes.com

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