"I can play all positions," Geathers said. "Been doing this all summer. Played it in Indianapolis. Played some in Dallas. This ain't nothing new to me."
It's likely that Logan would become the starter in the base defense. The team is also encouraged by the recent play of Geathers.
"It's my time to step up," Logan said. "My time, Clif's time, whoever the coach calls, it's our time to step up without Isaac here."
The Eagles also can use Cedric Thornton at nose tackle. Thornton and Fletcher Cox are the starting defensive ends.
Square, an undrafted player, has piqued the Eagles' interest in practice. He played in a similar 3-4 defense at Alabama and is technically sound on the line.
Kelly said Sopoaga did a "nice job" with the Eagles, but the coach thought the younger players deserved to play. That meant trading Sopoaga to New England after eight games despite a $3.25 million investment.
"I don't look at it that way," Kelly said. "I look at it as our three young guys are playing good football."
Quarterback Matt Barkley fumbled on a naked bootleg in Sunday's loss to the Giants. He said Tuesday that he had never run the play in practice. Kelly had previously said it was one of the top plays the team uses at the goal line.
"I said the team has [practiced it], so I don't think Matt was mistaken," Kelly said. "I think when you go into a game, your backup quarterback doesn't get a lot of snaps. . . . The backup quarterback doesn't get low [red-zone] snaps. We only snap the ball four times in the low red zone on Thursday practice, and all those reps go to the starting quarterback."
However, Kelly said Barkley has practiced naked bootleg plays before.
Wide receiver DeSean Jackson was limited at practice with an ankle injury.
Fellow receiver Damaris Johnson was out with an ankle injury. Linebacker Jake Knott (hamstring) and running back Chris Polk (shoulder) were also out.
Quarterback Michael Vick (hamstring), tackle Jason Peters (shoulder, finger), defensive end Cedric Thornton (knee), linebacker Casey Matthews (hip), and punter Donnie Jones (left foot) were limited.
Vick will not play on Sunday. Peters, Thornton, and Jones were all limited at this time last week with the same injuries and played in Sunday's game. Matthews was hurt against the Giants and is working his way back.