Brandt Clarke of the Kings scores past Bruins goalie Linus Ullmark in overtime to give Los Angeles a 5-4 win at TD Garden. Michael Dwyer/Associated Press

BOSTON — Brandt Clarke scored on a breakaway with 27 seconds left in overtime for his first career goal, and the Los Angeles Kings rallied to beat the slumping Boston Bruins 5-4 on Saturday.

Clarke had just been sprung from the penalty box for taking down David Pastrnak and was all alone when he skated in on Linus Ullmark and slipped the puck past the Boston goaltender.

“My heart was racing for a while in the penalty box, and I think from when I touched it at the red line to when everyone was jumping on me, I don’t even really remember that section but that was pretty wild,” said Clarke, who was mobbed by teammates celebrating both his first-ever goal in 17 NHL games and the comeback by the Kings.

David Rittich stopped four shots in overtime and the Kings successfully killed the hooking minor on Clarke before his game winner.

“It just happens like that sometimes. When they come out of the box, the puck comes there at the right time, you still have to finish that. That to me is the most impressive part of that,” Kings interim coach Jim Hiller said. “You’re coming down, you’re a young guy, you’re on a breakaway in Boston Garden. You’ve got to finish it and he sure did that.”

Anze Kopitar tipped in a goal with 1:35 remaining to tie it at 4-all and force overtime. Matt Roy, Vladislav Gavrikov and Alex Laferriere also scored goals for Kings, who improved to 3-2 since Hiller took over for the fired Todd McLellan.

“Just up and down the lineup, you’ve got to give credit to everyone,” Hiller said.

James van Riemsdyk scored twice and added an assist for the Bruins, and Ullmark finished with 30 saves. Trent Frederic and Anthony Richard were the other goal scorers for Boston, which has lost five of six and four straight, all at home.

The Bruins were in good position to stop the skid when Pastrnak drew a penalty on Clarke with 2:36 left in OT, but they couldn’t capitalize during the 4-on-3 advantage that ate up much of the last few minutes of overtime.

“They’re a desperate team. They’re fighting for their playoff lives, and we’re going to get a lot of that now,” Boston Coach Jim Montgomery said. “Our desperation has not since the break matched our opponents’ consistently.”

Van Riemsdyk scored on rebounds twice in the first period, and Richard scored 13:04 in the second to put Boston up 3-1. The Kings pulled within 3-2 when a wrist shot by Gavrikov from the point deflected off Boston defenseman Kevin Shattenkirk and got past Ullmark.

It was the second two-goal game for van Riemsdyk since he signed with the Bruins as a free agent last summer. Van Riemsdyk also scored twice against Nashville on Oct. 14 in the second game of the season.Alex Laferriere, who played at Harvard, tied it with a goal 5:51 into the third.

Frederic swooped in for a rebound afer Rittich stopped Morgan Geekie from just in front of the crease and scored to put Boston back up 4-3 with 12:48 left in the third.

After Van Riemsdyk’s first goal, the Kings tied it at 11:02 when Roy got off a shot from the side of the net and the puck slowly crossed the goal line as Ullmark scrambled to stop it. Multiple players squared off when a scrum developed during the Kings’ celebration, and Andreas Englund, who joined Trevor Lewis with an assist on the goal, and exchanged punches with Frederic.

An apparent goal by Pastrnak was disallowed after the Kings challenged and officials ruled that Boston’s Jake DeBrusk was in the crease while fighting for position with Mikey Anderson. The review wiped out a great play by Pastrnak, who spun a full 360 degrees at the top of the right circle and came out of the spin with a wrist shot that beat Rittich to the stick side.