It could be a few days before he actually gets on the field.
The Jaguars placed Clemons on the active/non-football injury list Friday, a day after he failed to report for camp because of personal issues. He drove in from Georgia late Thursday night and joined teammates for meetings Friday morning. But it remains unclear when Clemons will take part in drills.
Coach Gus Bradley declined to reveal the nature of Clemons' injury - an unusual move for a guy who typically provides more information than others around the league.
''I wouldn't put any timetable on it,'' Bradley said. ''He's working out with our guys now and doing some things with them as we progress. It's good to see him back here. We had great conversations. Although it was a challenging situation, I loved the communication. Just very happy that, for the most part, things got taken care of. There are some things we still need to (do) with him personally, but he's here, and I appreciate that part of it.''
The 33-year-old Clemons, who had eight sacks last season and has 66 in his 12-year career, worked with trainers on the side as his teammates practiced for the first time in six weeks.
The team declined to make Clemons available following practice.
His absence is somewhat alarming for the Jaguars since they're already without defensive linemen Dante Fowler Jr., Sen'Derrick Marks and Cap Capi. Fowler, the third overall pick in the NFL draft, injured his left knee in May and had season-ending surgery. Marks is recovering from knee surgery and might not be ready for the opener. Capi is day-to-day with a hamstring issue.
Receiver Marqise Lee, meanwhile, was one of the bright spots for an offense that fumbled three times, dropped several passes and had an interception returned for a touchdown.
Lee practiced for the first time this year after missing all of organized team activities and minicamp with a left knee injury. Although he was overshadowed by fellow receiver Allen Robinson, Lee got open deep a couple of times and made plays despite an issue with his knee brace.
But just being available was a step in the right direction for Lee, a second-round draft pick from USC in 2014 and someone the Jaguars are counting on to help improve one of the league's worst offenses.
''It took some time,'' Lee said. ''Of course, I felt like I was ready to go early, but then again you've got to go through the trainers and how they feel about you recovering and how they feel about how you feel in general as far as you being 100 percent. They didn't feel like I was 100 until now. Now I'm out here getting it going.''
Lee took off his brace midway through practice because it kept sliding around. Trainers wanted him to wear it mostly for protection in case a teammate hit his knee or fell into it during practice.
''He did really well, just felt really confident,'' Bradley said. ''He's got some speed and he's got burst. It jumps out at you with Marqise. We challenge these guys to take away doubt with how they worked out in the summer. If they have no doubt, they'll have no fear. We want these guys to play with the absence of fear.''
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