The biggest thing Andy Reid left behind when he was fired after the 2012 season was a philosophy that he never strayed from.
To build from the inside out. To make the offensive line and defensive line the biggest priority aside from QB and worry about everything else next.
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After taking Donovan McNabb in 1999, Big Red had 11 more first-round draft picks, and eight of them were linemen.
Some were Pro Bowlers, like Corey Simon and Fletcher Cox, some were disasters, like Danny Watkins and Jerome McDougle.
But the philosophy was spot on. And Howie Roseman was there every step of the way watching and learning.
Doug Pederson was there for some of that too, and he and Roseman are in lockstep on this:
Get yourself an elite quarterback, figure out how to protect him, then figure out how to attack the opposing quarterback, and you're well on your way to building a championship contender.
Or a Super Bowl champion.
There are four holdovers on the Eagles' roster who've been here since the Reid Era - Cox and Brandon Graham on defense, Jason Kelce and Jason Peters on offense.
Four linemen. No surprise there.
As long as Roseman is here, this philosophy won't change. The lines will always be the biggest priority. You can find running backs and receivers. You can find corners and linebackers.
But none of it matters if both lines aren't big-time.
And with free agency still a day away, the Eagles have already taken steps to upgrade or solidify both lines.
Think about it.
Until the DeSean Jackson trade, each move the Eagles made involved one of the lines. Extending Jason Kelce and Isaac Seumalo. Restructuring Lane Johnson. Giving Jason Peters another year. Giving Brandon Graham a three-year deal. Cutting ties with Tim Jernigan. Trading Michael Bennett. Signing Malik Jackson.
The Eagles are a better team today than they were a week ago.
Securing Kelce amid questions about his future was huge. Peters is a big question mark because of his injuries, but be honest - would you rather have Jason Peters at left tackle or Big V? Jordan Mailata is the left tackle of the future, but don't bet against Peters being able to crank it up for one more big-time year. And Seumalo got an extremely team-friendly deal for a versatile and capable pro.
On the D-line? Cutting ties with Jernigan and Bennett cleared $14.2 million in cap room and the Eagles have replacements for both. There's no reason to think Derek Barnett can't do what Bennett did or more - for half the price and a decade younger. Graham is a bit of a risk because of his age, but healthy again I think he'll be his usual effective, whistle-to-whistle self.
The key to all of this is Malik Jackson. He's a beast.
The second defensive tackle was a real liability for the Eagles last year. They used four different starters, but none of them was effective.
Opening-day starter Destiny Vaeao did little, Jernigan was out virtually all year and Haloti Ngata proved to be only a shadow of his one-time all-pro self. Practice squadder Treyvon Hester showed a little promise but is best suited to be a role player.
Opposing offensive coordinators didn't even have to account for those guys.
Now Cox has a guy next to him who's a legit NFL defensive tackle, a 6-to-8 sack guy, and that's only going to make Cox more dangerous.
The Eagles have improved on the offensive line, and they've improved on the defensive line, and they've also added an explosive wide receiver, and they've done it all without destroying their salary cap and without hurting their 2020 compensatory pick haul.
This is what Roseman does.
The Eagles are a better team than they were a week ago.
And free agency and the draft haven't even started.
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