The Washington Capitals will most likely be without their top defenseman for a second straight game, as John Carlson was not at morning skate on Wednesday and had an MRI exam on his lower-body injury. Coach Barry Trotz didn’t officially rule him out for the game against the Buffalo Sabres, as he doesn’t know the results of the tests yet. The results will also determine if Carlson travels with the team to Carolina on Thursday.

“We just wanted to take a look at his injury,” Trotz said. “We’ll see where he is when he gets back here. I was going to keep him off [at morning skate] anyway. We’ll see when he gets the results. … They’re doing everything to make sure the player is in good health, so we had an opportunity this morning to do that.”

Carlson skated briefly and gingerly before the team’s morning skate on Monday in Buffalo. Trotz said he “got twisted up” in Washington’s game against Montreal on Dec. 26. After taking warmups and pregame rushes on Monday, Carlson was scratched, and Trotz said after the game he thought Carlson was “pretty close” to being able to play again.

The injury to Carlson puts a greater strain on a defense that’s already been playing more than a month without a top-pair defenseman, as Brooks Orpik has missed 21 games with a lower-body injury. For Carlson, not playing on Monday broke a streak of 412 consecutive games played.

“If John could play, he would play,” defenseman Matt Niskanen said. “He doesn’t show it, but I think it’s kind of killing him inside that he broke that streak.”

Carlson, 25, is on pace to have his best season, with six goals and 21 assists this season. He also plays on both the first power-play unit and on the penalty kill, logging the most minutes per game. Karl Alzner and Niskanen became the top pair in his absence on Monday, logging the most minutes in a game this season, as Alzner had 26:23 and Niskanen had 27:25.

Alzner said after Washington’s 2-0 win at Buffalo that the greater minutes were hard on him. The second pair was Nate Schmidt with Dmitry Orlov and third pair became Taylor Chorney and Connor Carrick.

“[Alzner] was saying that he wasn’t feeling good, he felt like he was trying to survive those extra minutes and wasn’t pacing himself,” Niskanen said. “He just didn’t feel like he had the jump that he normally would. But sometimes it’s weird where if you play more minutes you even feel better and that’s what happened to me the other night. I think it’s just how the game goes and what kind of minutes they are.”