ALLEN PARK -- Detroit Lions running back Jahvid Best has not yet been cleared for contact and will start training camp on the physically unable to perform (PUP) list. He will join rookies Chris Greenwood and Ronnell Lewis on the sideline.

Additionally, rookie wide receiver Ryan Broyles and offensive tackle Jonathan Scott are on the active/non-football injury list.

Best has been out of action since suffering a concussion against the San Francisco 49ers in Week 6 last season. He was placed on injured reserve a couple weeks later and finished the year with 390 yards rushing, 287 receiving and two touchdowns.

Best had been a full participant for the Lions' OTAs and mandatory minicamp, but those were non-contact practices.

Speaking to the media on Thursday, Lions coach Jim Schwartz said the team is taking full precaution before getting Best back on the field.

"It's not just one single thing," Schwartz said. "It's sort of a whole battery and a whole process. There a lot of people involved in that. It's just not one single point of contact. He has input from a lot of experts around the country, not just our team doctors, but like I said, national experts."

Best is eligible to come off the PUP list as soon as he is cleared for contact.