T.J. Watt’s status for the Pittsburgh Steelers’ game Monday night remains in question because of a lung ailment that required a stay at a local hospital.

Watt remained away from the team Friday while the Steelers continued preparations for their game against the Miami Dolphins at Acrisure Stadium.

If the 31-year-old outside linebacker is unable to play, it would end a streak of 56 consecutive games started, and it would remove a former NFL defensive player of the year from the Steelers defense. And it also would transpire with the Steelers trying to plug a leaky run defense while trying to maintain control of first place in the AFC North.

If there is one positive, it’s that the Steelers have grown accustomed to filling in at the outside linebacker position this season. Alex Highsmith missed two games early in the season with an ankle injury and two more in the second half because of a pectoral strain. Top backup Nick Herbig sat out the season opener with a balky hamstring.

“I know T.J. has full trust in me and the group that we’re going to be able to pick up the slack for him,” Herbig said Friday. “Obviously, you can’t replace a guy like that, a Hall of Famer, one of the best in the league to do it. It’s hard to replace a guy like that, but we’re going to do everything in our ability to make sure we do the right things by him.”

Since Watt entered the league in 2017, the Steelers are 1-10 without him in the lineup. But given the presence of Highsmith and Herbig, they might be better equipped to fill his void this season. Watt may lead the Steelers with seven sacks, but Highsmith and Herbig are right behind with 6.5 sacks apiece. Rookie Jack Sawyer, whose role would increase if Watt is out Monday, has one sack in limited playing time.

The Steelers weathered Highsmith’s absence by going 3-1. They beat the New York Jets in the season opener with Herbig watching from the sideline.

“I’m not worried at all because we have great guys, great leaders that will pick up the slack,” Herbig said. “I think T.J. has prepared not just myself but the young guys in that sense — to be able to take on a larger role, not just as a player but as a leader and bring that energy.”

Highsmith has dealt with his share of injuries and was limited to 11 games last season after hurting his groin. When healthy, though, he has been a consistent pass rusher. Highsmith’s 6.5 sacks have come in just nine games and are a half-sack higher than his total from last season. With one more sack, he will have the second-highest total in his six-year NFL career.

Highsmith had two sacks in consecutive games prior to his pectoral injury. After being shut out in a loss to Buffalo, Highsmith put an emphatic end to the Steelers’ 27-22 victory in Baltimore last weekend when he sacked Lamar Jackson on the final play of the game.

“Alex is one of those players that can play run or pass. There’s not a deficiency in his game,” defensive tackle Cameron Heyward said. “The conversations we have in studying our opponents, he’s really just stepped that up this year, especially. We’re just going to need more of it. We’re looking for him to step up as a leader in that group, with Nick and Jack as well.”

Herbig has gone three games without a sack but has set a career high with 6.5 while playing 61% of the Steelers’ defensive snaps. His ascension has enabled the Steelers to use more three outside linebacker sets on defense — when he, Watt and Highsmith have been healthy. For that to continue, Sawyer will need to take on a heavier workload.

Sawyer has played just 11 snaps combined in the past two weeks, the lightest usage of his rookie season.

“I feel like I’m getting better each week and getting more comfortable in the scheme,” Sawyer said.

With or without Watt, the Steelers will face a Dolphins team that has exceeded 150 yards rushing each week while compiling a four-game winning streak. That was capped by a 239-yard performance last weekend in a 34-10 victory against the New York Jets. The Steelers, meantime, are trying to regroup after allowing 217 rushing yards to the Ravens a week after the Bills gouged them for 249.

“The run defense is a concern,” Heyward said. “We’ve got a hell of a challenge.”

Perhaps not coincidentally, the Steelers’ struggles coincided with the absence of first-round pick Derrick Harmon with a knee injury. In the four games Harmon has missed because of injuries, the Steelers have yielded 191.3 rushing yards per game. When Harmon plays, the defense has allowed 96 yards on average.

“Derrick is very stout,” Heyward said. “We have guys that are learning and coming along. But it’s kind of the same with T.J. You can’t just go out there and replace him. You’ve got to have other guys step up. It’s more done by committee.”