OXNARD, Calif. – The Cowboys have made several roster moves to open training camp, headlined by the decision to place Rolando McClain and Darren McFadden on the physically unable to perform list.

The news comes one day after Cowboys officials hinted that the team has several candidates for the PUP – though none of them are considered serious problems.

McClain is still in the process of rehabbing his offseason knee surgery, which limited him during OTAs and minicamp. Cowboys coach Jason Garrett said Wednesday that the linebacker would likely be limited in the early going.

"Rolando's coming off a couple different things that he's dealt with over the offseason. And initially he's probably not going to be practicing very much," he said. "He did very little with us over the offseason. He was trying to rehab that knee. He'll still be in that mode. He looks good physically, but he's probably not going to be on the practice field right at the outset."

McFadden was hindered by a hamstring injury during the spring, and that same hamstring will limit him to start training camp.

Unlike the regular season PUP, the Cowboys can activate players from the PUP at any time during the preseason. The hope is that McFadden can be moved to the active roster after he's had some extra time to monitor the injury.

"Just because a guy starts on PUP doesn't mean he'll be there long," said Cowboys executive vice president Stephen Jones. "A lot of times they start there to get a good feel for them and then move right off. I don't expect it to be a difficult situation for us on the numbers of PUP."

In addition, the Cowboys moved veteran linebacker Keith Rivers to the reserve/retired list, opening up a roster spot in the process. Rivers signed a veteran minimum deal during free agency, and he was considered a candidate for the strong side linebacker job that was vacated by Bruce Carter.