BETHLEHEM -- Eagles defensive tackle Cullen Jenkins said his hamstring problem is "just a tweak" that won't sideline him long.
Jenkins agreed it is strange having all four projected d-line starters injured right now. "We have our defensive line meetings in the training room," Jenkins joked.
Injuries to Jenkins and the other starting defensive tackle, Mike Patterson, whose skull is healing after surgery, have put the focus even more squarely on first-round rookie Fletcher Cox.
"Going through the OTAs and everything, he was in [Juan Castillo's defense] but not able to go full speed or anything," Jenkins said of Cox. "it kind of hinders you a little bit in the learning process. Now that you're coming out here it's full speed, and it's just a little bit different."
Indeed, Cox said Thursday his biggest hurdle has been the speed of the afternoon practices, as he tries to put into motion what Castillo and defensive line coach Jim Washburn are telling him. "It's kind of a shock," Cox said.
There is an excellent chance Cox starts the preseason opener Aug. 9 vs. the Steelers.
"I'm kind of thinking about it. I know coach Wash, he'll have me prepared for it," Cox said. Second-round defensive end Vinnny Curry is in a similar situation, with Jason Babin (calf) and Trent Cole (AC joint) sidelined.
"I just want to take these next few days like studying for a test," Curry said. "Some things, you just got to make sure you're ready for."
The Eagles made a positional change at the morning walkthrough. Jamar Chaney confirmed he is practicing Thursday as a starter in the nickel, supplanting Brian Rolle. Going into camp, it seemed second-round rookie Mychal Kendricks was going to be the nickel starter alongside DeMeco Ryans, but in camp that has been more Rolle, who starts on the weakside in the base.
Chaney said he took working with the second team until now as a way to improve, working against the first-team offense more than the defensive starters do.
"That's got to build confidence a little bit," he said. "I'm going up against some of the best pass-receiving running backs in the league" in LeSean McCoy and Dion Lewis.
Chaney said he wasn't given a rationale for the move. At 6-feet, 242, he is bigger and more experienced than Rolle or Kendricks.
"I started every game last year, had a lot of competition against great quarterbacks and whatnot," Chaney said. I think I'm only going to get better."
Evan Mathis sat out the Thursday walkthrough because he was feeling ill. Dallas Reynolds stepped in.