John Carlson’s ice time has surged this season. (Nick Wass/Associated Press)

Three minutes eight seconds into the Washington Capitals’ game against the Toronto Maple Leafs on Tuesday night, defenseman John Carlson had already spent 2:30 on the ice. After 40 minutes, Carlson had played roughly half the game. By the end, he had skated 27:33, a season high but a new normal. It marked the fifth straight game Carlson was on the ice for at least 25 minutes.

“You don’t feel it until you get home,” he said.

Carlson has never had to play more for the Capitals; he’s averaging 26:13 per game through the first seven contests of the season. That’s up more than three minutes from last season and nearly two minutes from Carlson’s previous career high for time on ice (24:31 in the 2013-14 season). After the offseason departures of defensemen Karl Alzner, Kevin Shattenkirk and Nate Schmidt, Carlson was already being taxed more to start the season, and a hand injury to Matt Niskanen guaranteed Carlson’s ice time would stay elevated at least until Niskanen returns to the lineup sometime next month.

With Carlson in a contract year, this being his eighth full season in the NHL, the Capitals are selling his elevated ice time as a good challenge for a player who wants to show he’s an elite, No. 1 defenseman. But as veteran blue-liner Brooks Orpik candidly put it, “He doesn’t really have a choice right now, to be honest with you.”

This is the most Washington’s blueline depth has been scrutinized under Coach Barry Trotz. The Capitals are allowing 3.43 goals per game and 33.9 shots per game, up from 2.16 and 27.8 last season, when Washington was the best defensive team in the league. With Carlson now consistently on the ice for nearly half the game, his play is under the microscope.

“John is obviously a very talented defenseman,” Trotz said. “This is his opportunity to showcase himself in a lot of ways. Can he be an elite defenseman for us? Can he handle heavy minutes and play at a high level? … That’s where we need him to be.”

It seemed Carlson was progressing toward this step after a career year during the 2014-15 season, posting 12 goals and 43 assists to finish in 10th place in Norris Trophy voting as one of the league’s top defensemen. But after Carlson played in 412 consecutive games for the Capitals, two injury-plagued seasons followed and he never regained his top form from three seasons ago.

“I think that now he’s back to being healthy and really starting to get into the challenge of playing even higher minutes than he has in the past,” associate coach Todd Reirden said. “… John’s at his best when he’s on his toes and attacking. I think that allows him to dictate how the game is played instead of letting somebody come at him. That’s definitely key for him, whether he plays 18 minutes, 22 minutes or 26 minutes.”

When Reirden and Carlson have reviewed video of Carlson’s shifts in the past three years working together, Reirden has suggested Carlson watch the opposition’s defensemen in those clips, especially top blue-liners like Erik Karlsson, Drew Doughty, Ryan Suter and Kris Letang. They all averaged more than 25:30 per game last season. When Washington boasted one of the deepest and most balanced defense corps in recent years, the team didn’t need Carlson to take on that kind of a load. But now that it does, the challenge is maintaining a strong level of play even with more time for error.

“You’ve just got to make sure that you’re putting the same enthusiasm and effort into every shift that you would with whatever the time difference is,” Carlson said. “… You’ve got to not manage the game; you have to attack it. I think that’s the biggest thing that the best do: They don’t take a couple shifts off here or there and just make a no-brainer play and float around a little bit. It’s just having the mind-set to attack each shift, and you’ve got to keep your level at the same level as if you were playing less.”

Carlson mans the Capitals’ top power-play unit, is one of the first defensemen over the boards on the penalty kill and faces the opponents’ top goal-scorers at even strength. He’s also being counted on to lead some of the team’s younger defensemen, with Washington’s lineup currently featuring two rookies. Perhaps that’s the biggest change for the 27-year-old. Last year, he skated mostly with Alzner, and when he had his best season in 2014-15, Orpik was the veteran charged with stabilizing his young, promising partner in Carlson.

Now the role of stabilizer has shifted to Carlson when he skates with rookies Christian Djoos or Madison Bowey. Add it to the load he’s already shouldering.

“Top guys in the league play 25 minutes,” General Manager Brian MacLellan said. “It’s a really good challenge. It seems like he can handle it. We’ll find out here.”

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