The Lions placed three players on the active/physically unable to perform list to begin training camp Friday, including running back Jahvid Best.
Best wasn't cleared and hasn't participated in full team workouts since he suffered a concussion in Week 6 against the 49ers last season, his second in 2011 and third in his career.
Best said last month he was cleared for football activity, but coach Jim Schwartz said Thursday that Best isn't cleared for contact. Mikel Leshoure, a second-round pick in 2011 who missed last season while recovering from a torn Achilles suffered in August, passed his physical and is likely to work with the first-team offense along with Kevin Smith.
Schwartz said Best received input from experts around the country but continues to work with the Lions' doctors. He missed the final 11 games last season, including the first-round playoff loss at New Orleans.
Newly signed offensive tackle Jonathan Scott was placed on the non-football injury list. Scott signed Tuesday after being released by the Steelers. The Lions did not disclose a specific injury and he might be held out for conditioning reasons.
Rookie second-round pick Ryan Broyles was also placed on the NFI list.
Joining best on the PUP list are rookie cornerback Chris Greenwood and rookie defensive end Ronnell Lewis.