The unmistakable sound of boos, while scarce with attendance limited at Capital One Arena, came through clearly Saturday night near the end of the Washington Capitals’ 3-0 loss to the Pittsburgh Penguins.

It was the second game in three nights between fierce rivals missing some of their stars, and the Capitals produced no fireworks this time. Washington fell flat and was shut out for just the second time this season as Penguins goalie Tristan Jarry made 24 saves.

“I think, obviously, you’re going to have games like this, but even if they won, 3-0, I don’t think we played that bad,” Capitals center Nicklas Backstrom said. “We should have probably scored on our chances in the second there. It would have been a different game. In the third, felt like we couldn’t get anything going there.”

The Penguins (34-15-3, 71 points) are now alone atop the East Division; the Capitals ­(32-14-5, 69 points) are in second place with a game in hand. Each team clinched a playoff berth in the Capitals’ 5-4 overtime loss to the Penguins on Thursday. The Capitals, who are headed to their seventh straight postseason, finished 2-2-4 against the Penguins this season.

“Almost every game was identical,” Coach Peter Laviolette said of the season series. “The team that capitalized won the game. . . . [On Saturday] it was a couple things that happened, and they got a couple really good looks, and they put it in. That’s pretty much the way it’s been, for me. Every game’s looked the same. If we see them in the playoffs, it will look the same.”

Elsewhere in the East, the third-place New York Islanders (31-15-5, 67 points) clinched a playoff spot with a 3-0 win over the New York Rangers. The fourth-place Boston Bruins ­(30-14-6, 66 points) won, too, by thumping the Buffalo Sabres, 6-2.

Washington, which was without captain Alex Ovechkin and defenseman John Carlson because of lower-body injuries, ended up in a three-goal hole midway through the second period after two breakaway goals by the Penguins’ Bryan Rust and a goal that caromed in off Jeff Carter’s skate.

“He’s been a great player for us for years,” Jarry said of Rust. “It goes easy for him. . . . He’s scoring timely goals for us. I think we all have a sigh of relief when he’s able to do that.”

The Capitals generated more scoring chances late in the second period and had a few decent looks in the third, but they came up empty. Their one power-play opportunity arrived with 9:40 left, but the Capitals recorded only one shot.

“They took care of their opportunities, their bounces, and we didn’t,” Backstrom said. “[Jarry] was really good in net — that’s for sure. He played a great game.”

Capitals goaltender Ilya Samsonov had won four straight games coming into Saturday’s contest. He made 23 saves but fell to 13-4-1. He entered Saturday with a 2.67 goals against average. Rookie Vitek Vanecek, who was in net for Thursday’s loss, is 18-9-4 with a 2.75 goals against average.

Laviolette has maintained that his team will continue to rely on both goalies, but the Capitals have just five games left. Their next two are Monday and Wednesday against the Rangers at Madison Square Garden.

Samsonov’s first hiccup came on Rust’s first breakaway just 2:56 in. Garnet Hathaway fell down near the blue line, leaving Rust free to break down the ice on a near two-on-zero before Sidney Crosby pulled up and let Rust take it himself. He went glove-side to beat Samsonov.

Rust’s second goal came 26 seconds into the second period. He blocked Dmitry Orlov’s shot high in the Pittsburgh zone, skated past Orlov and outmuscled him before beating Samsonov again. It was the 100th goal of Rust’s career. Carter gave the Penguins a 3-0 lead with 9:17 left in the second when defenseman Kris Letang’s centering pass went off his skate and in.

Ovechkin’s absence was his fourth in a row since he was hurt April 22 at the Islanders. Carlson missed his second consecutive game; he appeared to be hurt when he blocked a shot Tuesday against the Islanders. Both have skated since their injuries, but they remain listed as day-to-day. Pittsburgh was without forwards Evgeni Malkin, Brandon Tanev and Evan Rodrigues, who was injured Thursday night.

Ovechkin hadn’t missed four straight games because of an injury since November 2009, when he missed a career-high six in a row with an upper-body ailment. Saturday’s loss was the Capitals’ first in regulation without Ovechkin this season; they fell to 5-1-2 without him. He missed four games in January after he was placed on the NHL’s covid-19 protocols list. This is the first injury that has forced him out of the lineup since March 2015.

Without their captain and their top defenseman, the Capitals couldn’t get much going.

“Obviously, they’re a good team,” Backstrom said of the Penguins. “They were playing good defensively. Tough loss.”

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