LOS ANGELES -- With the Los Angeles Kings desperate to keep pace in the Western Conference playoff race, they got a decisive play from an unexpected source to win a pivotal game.

Adrian Kempe's first NHL goal proved to be the game-winner in the third period and Anze Kopitar added a goal and an assist as the Los Angeles Kings defeated the Washington Capitals 4-2 on Saturday.

The Kings (33-38-6) won their second straight game to remain three points behind the St. Louis Blues for the second wild-card berth in the Western Conference. Jonathan Quick stopped 17 shots.

The Capitals (44-16-7) lost a season-high third straight game and have not won in Los Angeles since Dec. 14, 2005. Their Metropolitan Division lead shrunk to one point over the Pittsburgh Penguins. Jakub Vrana and T.J. Oshie scored goals for Washington. Philipp Grubauer made 18 saves.

Kempe was matter of fact on his first career marker in his 11th game in a Kings uniform. He registered four assists but had yet to break through until Saturdayt.

"It was a really big goal so it was an extra good feeling," Kempe said. "I have had chances before, so I probably should have scored by now."

While Washington threatened when they had scoring chances throughout, Los Angeles limited the amount of scoring chances with sturdy five-on-five defensive play.

"You have to be good at all three positions. You look at the forwards and they're providing the back pressure which allows us to stand up and take away a lot of their rush play," said defenseman Alec Martinez. It's no secret they generate a lot of opportunities off that. We had some big saves from Quick, so just taking their time and space away, that's the key to high powered offenses like Washington."

The Capitals continue to play mediocre hockey since their bye week and their current losing streak has made a race out of a division that most thought the Capitals would breeze to just a few weeks ago. Why there is concern, there is little panic in the Washington locker room.

"There's obviously frustration, but we can't whine and cry about it like babies," said Justin Williams. "We've lost three in a row. Big deal."

With 15 games remaining in the regular season, the Capitals are aware that oftentimes the teams that play well down the stretch have a better chance of doing well in the post season. The fortuitous bounces that went that were going their way earlier in the season are not now.

"We hit two posts almost inside of the post in the second," said Lars Eller. "A month ago, those were going in for us."

Jeff Carter added an empty-net power play goal, his 31st of the season, at 19:58 of the third period to close out the scoring.

Kempe gave the Kings the lead for good at 8:46 of the third period. He deked Marcus Johansson and Dmitri Orlov to create space and fired a wrist shot past Grubauer. Kevin Gravel and Jake Muzzin drew assists.

The Kings evened the game at 2-2 on Kopitar's ninth goal on the power play at 7:20 of the middle frame. Kopitar deflected Carter's snap shot from the left faceoff circle off a feed from Muzzin.

Washington regained the lead at 2-1 on Oshie's 26th goal of the season at 47 seconds of the second period. Oshie converted the rebound of Johansson's attempt after he walked around Kings defenseman Derek Forbort.

Los Angeles tied the score at 1 on Marian Gaborik's ninth goal of the season at 15:30 of the first period. Kopitar got free inside the Washington zone and his initial try was stopped by Grubauer. Gaborik trailed the play and converted the rebound to register goals in consecutive games for the first time this season.

Washington took a 1-0 lead on Vrana's third goal of the season on the power play at 4:35 of the first period. Vrana was left uncovered to the right of Quick and shoveled Kevin Shattenkirk's pass from the blue line for the score with Justin Williams drawing the secondary assist.

NOTES: Washington did not dress D Taylor Chorney and Nate Schmidt. ... The Capitals conclude their three game California trip tomorrow in Anaheim. ... Washington is 14-6-0 against the Western Conference this season. ... Los Angeles scratched D Brayden McNabb, C Nick Shore and C Jordan Nolan. Gravel spelled McNabb on the blue line after being a healthy scratch for four games. ... The Kings killed 50 of 53 penalties over their past 21 games, the best in the league during that span. ... Los Angeles has a critical game against St. Louis on Monday, their fifth contest of a seven-game homestand.