Capitals defenseman John Carlson (74) celebrates with teammates after scoring a goal against the Ottawa Senators this season at Verizon Center. (Geoff Burke / USA TODAY Sports)

BUFFALO — On Monday morning, Karl Alzner was sure his friend and fellow defenseman John Carlson would play against the Buffalo Sabres. It looked bleak, as Carlson had gingerly skated around before the morning skate, but then didn’t participate in it. Washington Capitals Coach Barry Trotz said he would be a game-time decision with a lower-body injury.

But this was Carlson, on an iron-man streak of 412 consecutive games, just 10 away from matching the franchise record. Alzner was betting on the guy he saw play through all sorts of ailments in their five-plus seasons together.

After taking warmups and pregame rushes, Carlson was scratched, and Trotz said he is “pretty close” to being able to play again. Trotz said Carlson told him, “I’m probably not going to be able to help you the way I want to” after the warmups.

Alzner is now the player with the long consecutive-games streak still active, as Monday night marked his 411th straight game.

“It’s not something that anyone comes into the league looking to do, I don’t think,” Alzner said. “You know that it’s very, very unlikely that it’s going to ever happen. I don’t know how much he cares about it deep down, but if he does care about it, I feel bad for him.

“We’re at the point now, almost halfway, where if we have injuries, we need to be smart about it and don’t need to have anything lingering. If it’s something that you can’t quite get through or you’re not going to be able to help the team, then he makes the right call. He knows his body.

“It would be nice to have another guy to take that spotlight off of me because that’s what he was doing. It was perfect. But I guess it is what it is now.”

Carlson 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. Trotz praised the performance of Taylor Chorney and Nate Schmidt in stepping up in Carlson’s absence. Alzner and Matt Niskanen logged the most minutes in a game this season, as Alzner had 26:23 and Niskanen had 27:25.

The Capitals cancelled practice on Tuesday, so there won’t be an update on Carlson’s status until Wednesday, when the team has a morning skate.

“You play in this league and you get 400-plus games in a row, it’s pretty good now, especially for a defenseman when you can’t hold up like you used to and guys are taking free shots at you at 30 miles per hour,” Trotz said. “He’s pretty durable. He’s a big guy, and he’s a terrific talent. We missed him tonight, but guys stepped up.”