FRISCO — DeMarcus Lawrence had his leg resting on a scooter and took off for the training room the moment reporters entered the locker room.

Micah Parsons wasn’t as quick. He was sitting in front of his locker, putting on a protective boot for his high ankle sprain, when he was surrounded.

“Yeah, it’s time to man up,” Parsons said. “For sure.

“I’m very confident in these guys.”

Next man up is a phrase uttered in every NFL locker room once a player goes down. Losing players to injury over the course of a season is inevitable.

But compensating for the absences of Parsons and Lawrence is a big ask for this Dallas defense.

Parsons is one of the league’s elite pass rushers. His injury typically takes two to four weeks. Mike McCarthy said the Cowboys are preparing to face Pittsburgh this weekend without their best defensive player.

Lawrence will be out even longer. The veteran defensive end suffered a Lisfranc injury to his foot. It won’t require surgery, but several people with knowledge of Lawrence’s status put the timetable for his return at four to eight weeks, with the back of that range the more likely target.

Dallas will place Lawrence on injured reserve in the coming days, meaning he will miss a minimum of four games, a person with knowledge of the club’s thinking told The Dallas Morning News. Discussions are ongoing, but the plan for now is to elevate defensive end Carl Lawson from the practice squad for Sunday’s game and bring in several players for a workout.

None come close to what Parsons and Lawrence bring to this defense.

“Those are two dynamic guys,” defensive coordinator Mike Zimmer said. “Good leaders, good team guys.

“We’ll have to make some adjustments and see how it goes.”

Parsons is a focal point for every opponent. Accounting for where he lines up and how to neutralize him is where the offensive game plan starts.

The Steelers won’t have that concern. There’s no one player the Cowboys can plug into his hybrid role. Zimmer said he will just have to figure out how he intends to use other players and come up with a plan that plays to their strengths.

It will be a collective effort, not an individual one.

“That’s it,” McCarthy said. “It’s not like you take one player and put him in and give him the exact same responsibility in reps that Micah had or what D-Law had. It’s going to be a combination of things.

“You let the game plan bring that to light.”

The injuries open the door for rookie Marshawn Kneeland and veteran Chauncey Golston to move into the starting lineup.

The Cowboys took Kneeland in the second round to be Lawrence’s heir apparent. It turns out his time is sooner than later.

The Western Michigan defensive lineman has gotten off to a good start. But he’ll get even more snaps now.

“He’s a hard playing dude, likes to get physical,” Zimmer said. “He’s very coachable and soaks up a lot of the coaching.

“He’s a really good guy. I’m glad we got him.”

Parsons talked to Kneeland on Friday and told the rookie he was going to need to step up until he was able to return. Kneeland took it the wrong way, thinking that Parsons was questioning whether or not he was ready for the added responsibility.

“You don’t understand,” Parsons responded. “When I say step up I don’t mean just playing.

“Like you got to lead now. You lost your two veterans. You got to lead, you got to carry these guys. You got to communicate, talk to them, like bring these other guys with you.

“You’ve got to be the guy for us.”

Golston has bounced from inside to outside in his four years with the Cowboys. In the words of McCarthy, the defensive lineman has worn a lot of hats.

He’s a defensive end now. Golston has played the run well from that spot but his pass rush has been limited.

“He’s going to get some more playing time and get more opportunities in the passing game,” Zimmer said.

Golston has just 4.5 sacks for his career. One of those came this season. Parsons said his teammate reminds him of former NFL defensive end Cameron Wake in terms of his build and wingspan.

“With his length and ability and the way he can pass rush, being able to utilize it, I think he can be very, very, very good,” Parsons said.

“Those long arms, the things he is able to do with them, he’s going to be very good. I’m excited to see how he performs.

“He’s always talking about waiting for his opportunity. He’s got one one. I’m waiting to see it.”

Lawson will be part of the rotation on the outside along with Tyrus Wheat. Since Lawson will be out of elevations after Sunday’s game, he’ll need to be placed on the active roster going forward. That leaves a spot on the practice squad to bring in another player.

But replacing Parsons and Lawrence? That won’t happen.

“Those guys are the motor,” cornerback Jourdan Lewis said. “They make this thing go. Especially when we’ve got guys that make players like that. It’s contagious how they play.

“It’s definitely hard and we’re gonna have to find ways to supplement that because there’s no way you can replace it. So you gotta go out there and find ways to attack offenses you know, without those guys.”

Catch David Moore and Robert Wilonsky as they co-host Intentional Grounding on The Ticket (KTCK-AM 1310 and 96.7 FM) every Wednesday from 7-8 p.m. through the Super Bowl.

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