WASHINGTON — The Washington Capitals were halfway through their game against Pittsburgh on Wednesday, and the Penguins had tilted the ice in their favor in dominant fashion. The Capitals already had tinkered with their forward lines plenty in the first month of the season, so for the first time since they were put together two years ago, defensemen Dmitry Orlov and Matt Niskanen were split up.

Niskanen can guess why it had to happen.

“It wasn’t going good for me and Orly, so they mixed it up,” Niskanen said. “I wasn’t given a reason why, but that’s my feeling.”

The Capitals can sense pieces of their game starting to come around even as the sum of it remains inconsistent. As Washington continues to search for its identity, the lineup shuffling has reached its defense pairs, seen as the team’s stable corps entering the season with no personnel turnover from last year’s Stanley Cup run. Forward trios change frequently while defensive duos tend to have more staying power, but over the past three games, the Capitals have treated their top four defensemen as interchangeable.

The Orlov-Niskanen pairing in particular was practically untouchable outside of injury for the past two seasons, and while they could be reunited at some point, they have skated more time apart than together in the past three games. Orlov has been with top defenseman John Carlson while Niskanen is beside left-shot Michal Kempny.

“There’s inconsistency with our whole group, and we’ve been trying to find the right mix that works,” coach Todd Reirden said. “Some of it is [defense] pairings, and some of it is even how we want to have five-man units playing together, looking at what gives us the best chance to succeed. [Niskanen and Orlov] are not at the level that they were playing at the end of last year, so we’re looking at some different combinations. But I’m always comfortable that when push comes to shove, that’s been our go-to pairing and they’ve been really successful in the highest-stakes games that there are out there.”

Before the Capitals’ poor showing in a 4-1 loss to the Arizona Coyotes on Sunday, the team had allowed just one even-strength goal in three games, though some of that was more a credit to goaltender Braden Holtby than Washington’s play. They’ve played the past six games without veteran defenseman Brooks Orpik, who has an undisclosed “lower-body” injury, and he’ll miss at least the next four games as he’s on long-term injured reserve.

With Orpik unavailable, rookie Jonas Siegenthaler will travel with the team on its four-game road trip this week to Minnesota, Winnipeg, Colorado and then Montreal. Barring injury, Washington is expected to continue dressing a third pairing of second-year blueliners Madison Bowey and Christian Djoos. And while there are shifts within games when Orlov will be on the ice with Niskanen and Carlson with Kempny, the Capitals are practicing in their new formations and they’re starting games that way, too.

In the past, when Washington has been looking for more offense because it’s trailing in a game, it might deploy Djoos with Carlson, but protecting a lead and playing against the opposition’s top forwards was almost exclusively a task for the Orlov-Niskanen pairing. Niskanen said that if he knew why they’ve struggled together, he “would’ve tried to fix it a lot sooner.”

When they’ve been on the ice together this season, the Capitals have taken just 44 percent of the shot attempts, according to Natural Stat Trick. That’s a drop from the two previous seasons, when Washington accounted for 52 percent of the even-strength shot attempts with Orlov and Niskanen out there.

“I’m not happy with how I’m playing, but the last few games, I feel better and kind of find how I can play,” Orlov said on Saturday. “I’m getting my confidence back, so I just stick with it, with my game, and try to just watch some shifts, you know? What I did wrong, what I did right and analyze my game, so I think that’s helped me with how I’ve played the last few games. I think we’re going to be fine.”

Assistant coach Reid Cashman, who works primarily with the team’s defensemen, said the change “is nothing more than trying to shake it up a little bit.” Similarly to forward trios, defensemen need some time to build chemistry and learn each other’s tendencies and decision-making in certain situations.

“Sometimes, some time apart is good as well,” Reirden said.

“I always laugh that we’re kind of immune from any blender for the forwards, how they change in and out a lot,” Carlson said. “At the same token, I don’t think we really care that much. I think we all can play with each other and feel comfortable doing that, so it’s not really an adjustment, at least for me.”

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