CHARLOTTE – The Panthers have designated defensive end Ryan Delaire as their one player this season eligible to return from injured reserve, but the Panthers have three weeks to decide whether to bring Delaire back.

Delaire returned to practice Monday, officially adding "designated to return" to his status. That starts a 21-day clock in which Delaire can practice. At any time during the practice window, the Panthers can add him back to the 53-man roster, or they can opt to leave him on injured reserve for the remainder of the season.

Delaire played in the first two games before injuring his left knee. He was inactive in Week 3 and was then placed on injured reserve on Sept. 27, eventually undergoing arthroscopic surgery. Fellow defensive end Mario Addison, the Panthers' leader with 6.5 sacks, is recovering from a foot injury suffered Thursday.

"I feel pretty fresh. It's been almost two months," Delaire said. "I feel way better."

Since 2012, NFL teams have been allowed to return one player placed on injured reserve to the 53-man roster as early as eight weeks after he was placed on IR. This season for the first time, the player didn't have to be identified immediately upon going on IR but is instead chosen by his official return to practice. Even if the Panthers choose to keep Delaire on injured reserve after his 21-day practice window concludes, Carolina can't designate a different player for return.

Delaire stands ready to answer the call.

"Stepping up and contributing, that's something I want to do," Delaire said. "I tried to do that at the beginning of the season, and even when I was hurt, I tried to do what I could to help.

"I feel like I can contribute and bring something to the team."