ASHBURN, Va. -- Washington Commanders defensive end Chase Young will miss at least the season opener -- and possibly more -- because of a knee injury he suffered late last year.

The timetable isn't surprising given that coach Ron Rivera on Tuesday said Young would take the most time of the four players placed on the physically unable to perform list. One team source had told ESPN earlier this month that Young would return mid-September at the earliest.

But Thursday was the first time Rivera publicly provided any sort of timetable for Young, the No. 2 pick in the 2020 draft. Washington's first regular-season game is Sept. 11. Young tore his right ACL on Nov. 14.

At one point, Rivera said Young would open the season on the PUP list, which means he would miss at least four games.

Players must sit out the first four games before practicing, but there is no set number of practices they must participate in before returning.

Rivera later amended that to say he knew only that Young "will not play the first game." However, there is a possibility he would open the season on the PUP list or injured reserve. He would miss at least four games if he goes on IR.

"It just depends on where he is. I can't tell you," Rivera said. "The doctor is the only one that can tell you.

"You guys want me to give you a number. I can't give you a number. I don't want to put pressure on the young man to try to hit a number that I can't give you."

Young needed a graft from his left knee to help reconstruct the ACL. That lengthened his recovery timetable.

"It was a serious injury," Rivera said. "He's doing everything he's supposed to. He's on time as far as where the doctors think he should be, and as he gets better and better we can update you. But right now, he's right where he needs to be."