LOS ANGELES -- The Boston Bruins continue to ride the feel-good wave of a midseason coaching change that appears to have salvaged the season. With a new voice in the room guiding them, they gained two points with a performance from an unexpected source against a team whose postseason hopes are moving the opposite direction.

David Pastrnak scored the decisive goal and Anton Khudobin made 27 saves as the Boston Bruins defeated the Los Angeles Kings 4-1 on Thursday.

The Bruins (31-24-6) won for the fifth time in six games under interim coach Bruce Cassidy and moved into third place in the Atlantic Division. Backup goaltending has been an issue for the team the entire season but Thursday, they got a strong performance in relief of starter Tuukka Rask.

Khudobin entered the game with a 2-5-1 record, 3.06 goals-against average and .888 save percentage. The Bruins, despite playing the second contest of a back-to-back set, gave him enough support to earn the victory against the offensively challenged Kings.

"Yes it's back-to-back games even though we just had our break so we were fairly refreshed," Cassidy said. "It's not easy to do in this league, play big heavy teams back-to-back. This is a good hockey club."

The key to the victory was Boston's defensive effort playing with a third-period lead, limiting Los Angeles to three shots in the final frame.

"We really tried to make sure we had numbers coming back and did a good job of getting pucks out of the zone," Boston's Brad Marchand said. "They did have a few opportunities in there, but Khudobin again was very strong tonight."

Los Angeles (29-27-4) lost for the sixth time in its last eight games, scoring only six goals in the defeats. The lack of offense that has dogged the Kings all season proved to be their undoing once again.

"We've just got to bury all our scoring chances,'' Los Angeles' Kevin Gravel said. "We had our chances tonight and I think, for the most part, we played a fairly decent game. We had some pretty good sustained pressure on them. We can't get frustrated because we're playing good hockey, we just need to bury our chances."

With the Kings offense floundering down the stretch, coach Darryl Sutter refused to comment if the team needs to add offensive talent by Wednesday's trade deadline.

They trail the Calgary Flames by four points for the final wild-card spot with a game in hand. Another uninspired offensive effort on Saturday against division rival Anaheim may force general manager Dean Lombardi to make a move.

"I can't answer that question, I don't make those decisions," Sutter said.

Dominic Moore and David Krejci added empty goals at 18:58 and 19:52 of the third period for the final margin.

Boston opened the scoring on Marchand's 26th goal of the season at 3:16 of the first period. The unassisted goal was the result of a turnover by Kings defenseman Jake Muzzin inside the Boston defensive zone.

The Kings tied it on Gravel's first NHL goal on the power play at 18:12 of the first period. Adrian Kempe won a puck battle and threaded a pass to Gravel. Alec Martinez drew the secondary assist.

Boston took a 2-1 lead on Pastrnak's power-play goal, his 26th of the season at 4:43 of the second period. Pastrnak one-timed a cross-ice pass from Ryan Spooner, and despite breaking his stick, his shot eluded Peter Budaj (21 saves).

The Bruins appeared to have a goal by Peter Cehlarik at 18:52 of the first period, but it was overturned after a video review ruled the play offside.

NOTES: Boston scratched C Riley Nash, D John-Michael Liles and D Joe Morrow. ... The Bruins conclude their four-game road trip in Dallas on Sunday. They return home Tuesday to face Arizona to start a stretch of five home games out of six contests. ... Los Angeles did not dress C Andy Andreoff and D Paul LaDue. ... Kings coach Darryl Sutter (1,263) surpassed Jacques Lemaire for 13th on the all-time games coached list. ... Kings G Jeff Zatkoff cleared waivers but has not yet been assigned to the Kings AHL Ontario affiliate, a move further signaling the return of injured starter Jonathan Quick. The team has 30 days to assign him to their minor league club or they must pass him through waivers again.