Cornerback Chase Minnifield and running back Tristan Davis will be spectators when training camp starts next week, according to a report.Aaron Wilson of the FOX Sports reported via Twitter that the two will start camp on the physically unable to perform list, meaning that they are unable to practice until they are cleared by medical staff. They will still count against the 90-man roster and they will be able to attend meetings and other team functions while they rehab their injuries.Davis has been in various training camps and practice squad since the Lions signed him as an undrafted free agent in 2009. He suffered a knee injury during minicamp and at the time, Mike Shanahan said that he expected him to be ready. We do not know if he is being held out for this injury or if something else happened.Minnifield, who signed a contract as an drafted free agent in May, had microfracture surgery on his knee earlier this year. Although he did participate fully in some drills during OTAs and minicamp, it is not surprising that the Redskins are going to hold him out to make sure that the knee is fully healed.