Junfu Han / USA TODAY NETWORK Lions rookie OL Christian Mahogany has began practicing on Tuesday and his 21-day evaluation clock has begun. The Detroit Lions are coming off their bye week and have slightly altered their practice schedule in Week 5, holding their first practice of the week on Tuesday. With this early practice comes some positive news on the injury front, as rookie offensive lineman Christian Mahogany has begun practicing. Mahogany contracted mononucleosis (often called mono) in the offseason and has been unable to practice with the Lions since rookie minicamp. With his condition limiting his availability, he required a significant amount of time to get back into football shape, only joining the team late in training camp to work with trainers on his rehabilitation. Unfortunately, he did not get to a point where he was capable of practicing and opened the season on the non-football-illness (NFI) list. Last week, ahead of the Lions’ Week 4 matchup with the Seattle Seahawks, Lions coach Dan Campbell noted that Mahogany was close to completing his rehabilitation and could potentially join the team once he was eligible. “Mahogany’s very close,” coach Dan Campbell said on Saturday. “He’s very close for us to have that conversation of, what time is it to begin to start his clock?” Because Mahogany was on the NFI list, he was required to miss the Lions' first four games of the regular season, but now that enough time has passed and he is indeed in football shape, he returned to practice on Tuesday. By returning to practice, Mahogany begins a 21-day injury evaluation period, where he is allowed to practice with the team without counting against the Lions' 53-man roster. When the Lions feel Mahogany is ready to play, they can add him to the active roster at any point. If his 21-day evaluation window expires, and Mahogany is not ready to join the Lions' active roster, Detroit will have the option to place him back on the NFI list, but he would not be eligible for re-evaluation, meaning his season would be over.