The Big Questions

1. We know the starters, but how much depth is there on the offensive line?

In 2013, the Eagles started the same five offensive linemen in all 16 regular season games. For any team, starting the same group in every game is an impressive feat, but it was even more impressive for the Eagles given the circumstances. Lane Johnson, the fourth-overall draft pick, was thought of as an instant starter, but it's sometimes difficult to foresee a rookie starting every game. Two of the other starters were coming off of major injuries. Jason Kelce was coming off of major knee surgery to repair his ACL and MCL, and Jason Peters was back to action after injuring his Achilles tendon not once, but twice.

Even with all of that, plus the fact that the Eagles executed their offense at a no-huddle place, the offensive line stayed intact for the entire season. The Eagles ran 1,104 offensive plays in 2013. Out of a possible 5,520 combined snaps for the five offensive line positions, the starters played 5,426 of them. The five starters missed a combined 94 snaps, 51 one of which came when Peters left the Green Bay game after just 10 snaps.

But how likely is it that all five starters play as much in 2014? Obviously, the hope is that they can all stay healthy again, but if they can't, who is going to step up? When Peters went down against the Packers, veteran Allen Barbre stepped in and played well.

Barbre is a veteran who is capable of playing both tackle and guard. We all know how much Chip Kelly values versatile players, and Barbre is a great example. He is the jack of all trades who can be plugged in just about anywhere on the offensive line. After Barbre though, the Eagles are very, very young when it comes to backup linemen. Julian Vandervelde, the Eagles' fifth-round draft pick in 2011, can also play both guard and center. Dennis Kelly started 10 games at tackle and guard for the Eagles in 2012, but he is coming off of back surgery. The Eagles also have a host of even younger players who haven't seen much if any NFL action. These players - Michael Bamiro, Matt Tobin and David Molk very well could be the right pieces to fill the backup roles, but it's difficult to say at this point.

2. Can the line be as dominant in 2014?

When Chip Kelly was hired as the Eagles head coach, it became very evident that the Eagles would be a team built on the running game, and that is exactly what happened. LeSean McCoy ran wild for 1,607 yards, the best rushing season in Eagles history. He won the NFL's rushing title and catapulted himself to the elite level of the league's rushers. And while McCoy was the one grabbing all of the headlines and media attention, it was his linemen that paved that way for his success. McCoy praised his linemen again and again throughout the season, and rightfully so.

While there were a number of plays where McCoy would improvise and give the defenders the old "shake and bake" move, many of McCoy's best runs came when he ran north-south instead of east-west.

Another staple of Kelly's offense was the screen play, and the Eagles ran a lot of them. Often times, the Eagles' screen plays featured misdirection and other exotic looks, but the offensive line was up to the challenge. The key to a good screen is getting the lineman out in front of the play as quickly as possible, and there are few - if any - NFL lines more athletic than the Eagles. Jason Kelce, who has since signed a new seven-year contract, was the catalyst of the line and while he isn't the biggest center in the league, he is probably the most athletic.

And while Kelce is an up-and-comer in the league with a very bright future, the Eagles have two members of the line who are arguably the best at their respective positions. According to Pro Football Focus, a website that grades players, Mathis is the highest-rated offensive lineman in the NFL. In fact, Mathis hasn't received one negative grade in his last 49 games. Not one. The man who lined up to Mathis' left isn't too shabby either. Since Jason Peters was acquired from Buffalo in 2009, he's been the best tackle in the NFC, if not the entire NFL. Like Kelce, Peters signed a new long-term contract this offseason. He then said in his press conference that he wanted to retire as an Eagle, and that thought should cause for many happy Philadelphia fans. 

3. What will the second season be like for Lane Johnson?

Johnson was plugged into the Eagles lineup at right tackle right out of Training Camp, and from there he never looked back. Did he hit some bumps along the way? Sure, but for the most part, Johnson's rookie season with the Eagles was a major success.

So what will be done for an encore? At some point before the season, Johnson will be asked if he is worried about a possible sophomore slump. After many rookies burst onto the season with flying colors their rookie year, opponents are able to better adjust to them in their second year. Johnson earned a positive grade from Pro Football Focus in eight of the Eagles' final nine games of 2013 (all of which were victories), but this year he is ready to become a "dominant piece on the right side." He has added some extra weight and is working on his lower-body strength in an attempt to enter his 2014 even stronger than he finished 2014.