DAVIE, Fla. (AP) -- Miami Dolphins defensive end Dion Jordan is now missing practice for two reasons.

Jordan is expected to be sidelined two to three weeks while recovering from minor knee surgery, and has been placed on the active non-football injury list.

Jordan had not yet been cleared by the NFL to practice after receiving conditional reinstatement Friday following a 15-month suspension for his latest violation of the league's substance abuse policy. He has been taking part in team meetings.

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The former No. 3 overall draft pick watched Sunday's practice from the sideline and was upbeat about rejoining the team under new coach Adam Gase.

"There are a lot of new faces," Jordan said. "Everything just seems kind of brand new. I'm just excited to get out here and be around the guys in the locker room and just have that opportunity to compete once again."

The Dolphins activated running back Arian Foster from the physically unable to perform list. The former Pro Bowler signed this month and is returning from Achilles tendon surgery.

Miami signed cornerback Brandon Harris and waived cornerback Tyler Patmon.

Gase hadn't met Jordan until his reinstatement, and they had a brief conversation when Jordan reported.

"I told him he has a fresh start with me," Gase said. "Whatever's happened in the past is irrelevant, and moving forward his job is to do everything that he has been told he has to do right. That checklist is fairly long. We're here to support him. I think we have a great group of people to try to help him moving forward."

Jordan said he has learned from his mistakes.

"I had a couple bumps and I had to overcome them," he said. "It was part of my journey as a person, first of all, and as a football player second."

The Dolphins didn't know about Jordan's knee injury until he was reinstated, Gase said. Jordan declined to say how it happened.

Jordan said he weighs 275 pounds, the same as before his suspension, which would suggest the Dolphins plan to keep him at end rather than moving him to linebacker. The underachieving Jordan has played in only 26 games with one start and three sacks.