ASHBURN, Va. — Chase Young is starting Washington Commanders training camp on the physically unable to perform list and is the furthest from returning among the team’s injured players.

Young, tight end Logan Thomas and centers Chase Roullier and Tyler Larsen won’t practice when camp opens Wednesday. There’s also no guarantee Young will be ready to play in the season opener Sept. 12 against Jacksonville, roughly 10 months since tearing the ACL in his right knee.

“Chase Young is probably the one that’s going to take the most time,” coach Ron Rivera said Tuesday at his annual news conference on the eve of camp. “It was serious, obviously, and any time you’re talking about an ACL it’s just down the line. We’ll have to wait and see on that one.”

Rivera does not expect offensive tackle Cornelius Lucas, placed on the non-football injury list with an illness designation, to miss much practice time. Young is another story.

The 2020 Defensive Rookie of the Year injured the knee Nov. 14 against Tampa Bay. After leading rookies with 7½ sacks the previous year, he had just 1½ before his second NFL season was cut short.

Doctors grafted part of the patellar tendon from Young’s left knee to help fix the tear. Rivera has refused to define a timeline for Young’s recovery, with the 23-year-old Ohio State product and trainers taking a methodical approach to the rehab process this offseason.

While Young had said he expected to be all in for Week 1, Rivera called that “an unfair expectation.”

“You put pressure on people to try and accomplish that and get to where they’re supposed to be before they should be, and it could cause something,” Rivera said. “With Chase, and for the most part all those guys, when they’re ready they’ll be back on the football field.”

Young was present for some spring workouts even though he hadn’t yet been cleared to practice. It’s not immediately clear how much he’ll be around while continuing to receive treatment. When he is ready, Washington expects Young to help the defense bounce back in the first season the team is known as the Commanders.

Until then, holdover Casey Toohill, young edge rushers Shaka Toney and James Smith-Williams and free agent addition Efe Obada will get chances to play opposite Montez Sweat.

“Until Chase is ready, we feel those guys have got to step up and produce for us,” Rivera said. “As far as Montez is concerned, we just expect him to play to his abilities. We don’t need more out of him than anything other than for him to do the things that he’s capable of. We need some other guys on the other side to step up.”

The Commanders expect Roullier, who broke his left fibula, to be the first player activated off the PUP list, followed by Larsen, who tore his left Achilles tendon. Thomas, who tore multiple ligaments in his left knee, should be back before Young because of the nature of the injury, Rivera said, though that could still take some time.

“Logan has looked really good,” Rivera said. “Not quite sure, but he’ll be down the line a little bit.”