PHILADELPHIA (973espn.com) - When Andy Reid arrived in Philadelphia back in 1999, the Eagles were not exactly steeped in a winning tradition.

To best exemplify that understand the NFC East was christened back in 1970 and in the nearly three decades before Reid took over the Eagles the franchise won only two division titles. In the two decades since Reid injected his DNA into the organization, Philadelphia has won eight division crowns, had 12 playoff appearances, reached six conference championship games, and earned a Super Bowl title back in 2017-18 with Reid acolyte Doug Pederson running things.

DNA

Except for the short detour that was the Chip Kelly disaster, which actually was responsible for one of those division titles, Reid's beliefs have been the foundation of the organization and according to former team president Joe Banner, building up front on both sides of the football was the first box Reid always wanted to be checked.

Over the last two seasons which have produced four postseason wins and a Super Bowl LII championship, the offensive line has been among the NFL's best with three Pro Bowl-level players and a future Hall of Famer in the waning years of his career.

There has also been chemistry and continuity starting with All-Pro center Jason Kelce, the cerebral, athletic pivot who sets the tone for highly-regarded offensive line coach Jeff Stoutland.

The tackles are All-Pro Lane Johnson on the right side and Canton-bound Jason Peters back for one more year as Carson Wentz's bodyguard. Inside is Pro Bowl right guard Brandon Brooks, rehabbing from a torn Achilles suffered in the divisional round playoff loss to New Orleans, and Isaac Seumalo, the one starter who hasn't reached star status but was given an extension in the offseason because the Eagles believe he has turned the corner.

PAVING THE LANE

Johnson has arguably been the best right tackle in the game over the past few years.

Last season was a struggle, however, as Johnson battled through two significant injuries, first a left-ankle sprain in Week 5 against Minnesota and then a more serious knee injury in London against Jacksonville, a multi-week issue for most but Johnson missed only a game helped by the bye week after the trip across the pond.

“Last year I played with a Grade 2 MCL and a high ankle, on my left leg," he explained.

And those injuries "took away a lot of power," according to Johnson. "Stuff I could normally do. ... That’s the [NFL] game. I feel good now, and I’m ready to go.”

The wear and tear from last season is the reason Johnson, about to enter his seventh season, decided to take a step back during voluntary work in the spring.

"Basically I was just trying to get healthy and get ready for the season,” Johnson said. “I really didn’t practice all [last] year."

A healthy Johnson is generally good news for the Eagles. During the Pederson era, Philadelphia is 30-11 when the University of Oklahoma product is in the lineup.

This week Johnson continued to work on his craft back in Texas during the NFL's downtime. He and offensive line development and scouting consultant Duke Manyweather, run the Offensive Line Masterminds get together in Dallas, an effort to create an atmosphere for NFL offensive linemen similar to what Von Miller has done for pass rushers.

DEPTH

The depth is impressive as well after the addition of first-round pick Andre Dillard, the obvious heir apparent to Peters at LT. His presence pushed former swing tackle Halapoulivaati Vaitai inside as the stand-in for Brooks at RG. With Week 1 the goal but very iffy for Brooks, Vaitai's move was a nod to his previous starting experience and probably a good indication that Philadelphia doesn't believe second-year player Matt Pryor is really for a larger role.

Interior backup Stefen Wisniewski could also play RG and is seamless moving between any of the interior positions. The Eagles know what they have in Wiz and want to see if they can get a little more from the bigger and more athletic Vaitai.

Jordan Mailata is taking the next step in what was always considered internally as a three-year project. He went from Australian rugby to NFL LT last season and played RT in the spring in an effort to ramp up his value and versatility.

Philadelphia also went heavy in the undrafted free agent market bringing in Sua Opeta, Ryan Bates and Nate Herbig, three players given draftable grades by many. Opeta got the second-team reps at LG in the offseason behind Seumalo and is a lock for the practice squad if the Eagles can get him through waivers.

DEPTH CHART:

OC Jason Kelce - The most athletic center in the game remains among the best offensive linemen in football.

RG Brandon Brooks - Still working his way back from the Achilles injury in the playoffs. Week 1 is very touch and go.

LG Isaac Seumalo - When this is your worst OL starter, you've got some nice problems.

RT Lane Johnson - Should return to All-Pro form after an injury-plagued 2018.

LT Jason Peters - The Bodyguard is back for one [presumably] last dance.

Swing Tackle Andre Dillard - The heir apparent to JP and a top-15 level talent who may need to play a bit to give Peters a blow here and there.

OT/IL - Halapoulivaati Vaitai - Vaitai was the starting RG throughout the spring as Brooks continued his rehab. Move inside is permanent with Dillard on hand.

Swing Tackle2 Jordan Mailata - Year 2 of a three-year plan has Mailata learning the right side.

ON THE BUBBLE:

Interior Backup Stefen Wisniewski - The Eagles know what Wiz can do. The question is can they find someone younger, cheaper and just as versatile?

IB2 Matt Pryor - The fact that Mailata was moved to the right side in the spring to fill in for Lane Johnson during voluntary work was not a positive sign but Pryor offers inside/outside positional flexibility.

IB3 Sua Opeta - A high-level UNFA signing out of Weber State, Opeta is regarded as a real prospect by Jeff Stoutland.

PRACTICE SQUAD CEILING:

OT5 Tyreek Burwell - Jeff Stoutland likes the athleticism and length of Burwell, who got LT reps in the spring.

OT6 Ryan Bates - The Eagles felt tackle should be the first spot for Bates but he may project inside long-term and even got some work as a 7-on-7 center. The more things you can do.

OT7 Casey Tucker - Late signing in the spring when the Eagles needed bodies during voluntary work.

IB4 Anthony Fabiano - Harvard product is smart and big at 303 pounds but the Eagles have gotten a bit spoiled by Kelce's athleticism inside.

IB5 Nate Herbig - Big Stanford product is more of a road-grader inside.

IB6 Keegan Render - The Eagles usually keep one center on the PS and Render, an undrafted rookie Iowa, is trying to push Fabiano.

POSITION GRADE: 9.0 [Unquestionably a top-five O-Line in the league, ProFootballFocus.com went as far as labeling the Eagles' big uglies as the top group in the entire NFL.]

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-John McMullen covers the Eagles and the NFL for 973espn.com. You can reach him at jmcmullen44@gmail.com or on Twitter @JFMcMullen