THE THEMES of this summer's Eagles camp have centered around injuries and rules.
Who can practice and, more importantly, who can't.
Who can touch who and when and where.
A year ago it was all about the breakneck pace of Chip Kelly's offense and how it would most certainly break some bones in the process, especially those who would play on his overtaxed defense. But then the season played out, the breakdown of bodies did not occur, and the themes shifted to Kelly's employ of the mysterious "sports science," which as far as anyone on the outside can discern, is a pseudo phrase for no more tacos.
And now? Now the daily discussions about who can practice and who can't, about timelines and injury severity, have dissolved those sports-science angles and at times, challenged the acerbic coach's patience. Like, when someone asked Kelly about the status of a sore toe that kept LeSean McCoy out of Sunday's practice the coach jabbed, "I don't think he'll ever play again.''
A few other answers about players unable to take the field also suggested a slight level of frustration from the coach. Wide receive Brad Smith's groin will not be healed in time for tomorrow night's game against the Steelers at the Linc, Kelly said. Nor will Josh Huff's sore shoulder.
Chris Polk, who seemed on the verge of becoming a meaningful piece at the end of last season, still cannot practice. "It's a big factor," Kelly said when asked about evaluating the third-year back. "You've got to be able to play.''
The challenge for the Eagles coach in his rookie season was that he didn't know what to expect. Now it's that he doesn't know who to expect. On Monday, the three starting receivers practiced together for the first time this summer. And when someone asked about Brent Celek again jumping to his feet after getting separated from his helmet in Friday's game againg New England, Kelly gushed about the tone of physical and mental toughness the veteran sets for the team.
"He's a guy I think you can count on on a daily basis,'' said the coach. "He's always out there - he loves playing football.''
Which brings us to DeMeco Ryans, the veteran inside linebacker who just might be the most indispensable player on this team. Yes, Kelly's offensive wizardry would be extremely taxed without McCoy and no one really wants to find out if a change of address is all Mark Sanchez really needed to regain his mojo. But Kelly has a rich and successful history in other places of replacing injured offensive pieces. And as tough as it would be to operate his scheme without his star running back and his emerging quarterback, there are at least some seasoned names to work with as their replacements, and some other weapons to compensate for it.
The same can not be said for replacing Ryans, though, which is one big reason he played in just 15 plays last Friday, and may not see too many more snaps against the Steelers. Ryans' 1,156 snaps were the most of any defensive player in the NFL last season. Only Tom Brady and eight offensive linemen played more, and if you eliminate the snaps Ryans missed at the end of blowouts, he skipped just three plays all season.
"He's kind of the face of our defense if not the whole program around here,'' linebackers coach Rick Minter said yesterday. "He's still our alpha dog.''
And while Kelly was reluctant to tab Ryans as his most indispensable, he did concede that, "If DeMeco gets hurt or sprains an ankle, there's obviously going to be an interesting transition in terms of who takes over for him.''
And while the thought of that is less frightening than it was a season ago, the depth chart at Ryans' position is still discomforting. Najee Goode, Casey Matthews and Emmanuel Acho are significant dropoffs, not just because of their limitations after the snap, but before it too.
"DeMeco just knows so much,'' safety Earl Wolff said yesterday. "He's a really smart guy. He's played in the game for a long time. He controls the whole defense. If the 'D' line is lined up wrong he knows exactly where to put them. If we give him a wrong call he'll turn around and say, 'No, it's this.'
"He kind of keeps everything flowing back there.''
Ryans yesterday practiced almost exclusively with second-string and third-string players. "Just so he could be teaching guys things,'' said Wolff.
The goal this year is to let the dog, who just turned 30, sit in the shade a little more, particularly on passing downs. That's why Malcolm Jenkins is here. It's why Nolan Carroll is, too. The Eagles' lack of secondary depth was so pronounced last season that Ryans was seen as a better option than any backup corner.
The Eagles were able to address that in the offseason. But they still don't have that backup quarterback to their alpha dog, and aren't likely to develop one in the final two preseason games. The hope is that they won't need to, that they are a bit more solid as a unit than they were a year ago.
The hope, too, said Minter, is that Ryans continues to prove indestructible.
" We're all renting our lockers here,'' said the coach. "We just don't know for how long. I just hope he's got a long lease.''
On Twitter: @samdonnellon