Nelson, 25, started three games for the Cincinnati Bengals as a rookie in 2009. He was limited by injuries in 2010 and joined the Eagles last December, playing four games. He came in too late to learn the defense but now has a better understanding of the scheme. He was encouraged by the depth-chart promotion, which he learned about Saturday.
"Of course I think I can play safety in the NFL," Nelson said. "I just need an opportunity."
That opportunity could come at the expense of Jarrett, a 2011 second-round pick out of Temple who struggled as a rookie. Even coach Andy Reid admitted there were troubling spots with Jarrett's tackling Thursday, but defensive coordinator Juan Castillo complimented Jarrett's camp to date.
"He got out there and started, and there were some good things and some things that he'll continue to work on," Castillo said. "You can't take away the training camp that he has had."
Maclin, Chaney return
Wide receiver Jeremy Maclin and linebacker Jamar Chaney missed Thursday's game and Saturday's practice, but they returned on a limited basis Sunday. They were on the field for part of practice before returning to locker room when team drills commenced. Both are dealing with hamstring injuries.
Rookie cornerback Cliff Harris returned to practice Sunday after missing a week, including Thursday's game, because of an ankle injury. Harris, who was impressive in camp before the veterans arrived, needs to be on the field to have any shot of making the roster.
Other players, such as defensive end Jason Babin and defensive tackle Cullen Jenkins, missed more practice time because of lingering injuries. The good news for the Eagles is that no one suffered any new injuries on Sunday.
Contact Zach Berman at firstname.lastname@example.org or follow on Twitter @ZBerm.