Kings’ youth beats the Blues

Life as a veteran NHL player in Los Angeles isn’t so grand these days. If the old hands aren’t on the trading block, they’re on the training table.

Those scenarios forced the Kings to get even younger Thursday night against the St. Louis Blues and the result was more proof that their youth is blithe.

Playing on the second line, Patrick O’Sullivan, Alexander Frolov and Michael Cammalleri combined for 11 points, leading the Kings to a 5-1 victory at Staples Center.

O’Sullivan, a second-year center, had a goal and four assists, Frolov, a fifth-year forward, scored three goals for the third time in his career and Cammalleri, also a fifth-year forward, contributed three assists.

“Guys got to step up and they did,” O’Sullivan said.

The one veteran who jumped into the act was goalie Dan Cloutier, who replaced injured Jason LaBarbera in the starting lineup and stopped 31 shots for his 345th career victory and second with Los Angeles this season.

“We all knew as a team how important of a game it was for them,” Cloutier said of the Blues. “They’re battling for a playoff spot.”

In addition to LaBarbera, who is day to day with a groin injury, 34-year-old center Derek Armstrong injured his knee two minutes into the game and didn’t return.

The oldest player on the team, 38-year-old Rob Blake, has been out since Feb. 2 with a fractured ankle and fellow defenseman Jaroslav Modry was traded to Philadelphia earlier this week for a third-round draft pick.

Kyle Calder, a 29-year-old forward, was a healthy scratch for the first time this season.

O’Sullivan, 23, assisted on three consecutive goals in a 2 1/2 -minute stretch of the second period, then added a power-play goal later in the period to give the Kings a 4-0 lead. The final goal ended the game for St. Louis goalie Manny Legace, who was replaced by rookie Chris Beckford-Tseu, who made his NHL debut.

“The bounces kind of went our way in that second period,” O’Sullivan said.

Armstrong came into the game seventh on the team with 29 points, but had been producing lately, accumulating 13 points in the last 18 games for a plus-five rating during that span.

Cloutier, recalled Feb. 7 to replace former backup J.S. Aubin, gave the Kings some breathing room with seven saves in the first eight minutes. He allowed a power-play goal in the final minutes to miss out on his first shutout in four years.

“At this stage, you just want to get the win,” Cloutier said. “Guys played extremely well in the third period. They didn’t really give them too many scoring chances. . . . That’s a great sign for a young team.”

dan.arritt@latimes.com