In 2011, Jason Kelce was the only member of the Eagles' offensive line to start all 16 games at one position. As a rookie, he was a model of durability while going through a positive learning curve performance-wise. As a result, more responsibility has been placed on Kelce this offseason when it comes to how the Eagles will operate from the time the huddle breaks to the time the ball is snapped. While Michael Vick was responsible for almost all of the pre-snap assignments and checks last season, most of that responsibility has now been given to Kelce. But while the Eagles hope Kelce can go on a Runyan-like run of consecutive starts, like any team in the NFL, they also must be prepared for the worst.

Last season, the job of Kelce's understudy went to Jamaal Jackson, himself the Eagles' long-time center. Now, the man for that job has not yet been determined. In fact, for an Eagles roster that features few true position battles, especially those without a known incumbent, the race for backup center is among the most interesting of Training Camp and the preseason.

"That's not even something that I'm worried about," said Kelce. "As a matter of a fact, if I'm worried about anything, it's that they're going to take my job. All three of them, if I ever went down for whatever reason, they could step in at center. That's something that's probably a luxury that most teams don't have."

Let's meet the three contenders who have earned Kelce's confidence.

The Last Chance

After 15 games on the practice squad, Dallas Reynolds was promoted to the active roster before the Eagles' season finale against the Dallas Cowboys. He didn't dress for the game, nor for the playoff rematch the following week. That was 2009, Reynolds' rookie season after he joined the Eagles as an undrafted free agent out of BYU. In 2010, Reynolds spent the entire season on the practice squad. In 2011, Reynolds spent the entire season on the practice squad. Now, with his practice squad eligibility exhausted, Reynolds must make the 53-man roster outright.

"He's got to make the team," said Kelce. "Absolutely (I sense an urgency). I think Dallas is in a good position because he's done so well on practice squad and he's really done a good job of taking hold of the center position as well, not to mention guard."

For three years, Reynolds has been about as faceless as one can be as a professional football player. A practice squad player, on the offensive line no less, isn't going to garner much attention. So what do we know about the 28-year-old Reynolds?

"Dallas Reynolds has been getting better every day since he got here," said offensive coordinator Marty Mornhinweg.

For one thing, adjusting to seeing the field only in the preseason has not been easy for Reynolds, who started all 51 games of his college career, split between all five offensive line positions. Over the last three seasons, Reynolds has sat and learned behind the likes of Jamaal Jackson, Nick Cole and Jason Kelce. He's also had to adjust from Juan Castillo's techniques to the more aggressive pass-blocking stylings of Howard Mudd.

But through it all, Reynolds has remained patient and hopeful that he would earn his way onto a permanent spot with the Eagles.

"I'm just trying to do the best I can," Reynolds said. "I've been here for a couple years, so I'm just trying to put my foot in and make the 53. So that's all I'm really focused on, playing well."

Throughout Training Camp thus far, Reynolds has worked as the second-team center behind Kelce. Then, on Thursday, with starting left guard Evan Mathis out with an illness, Reynolds took reps with the first-team defense at Mathis' position.

"He's a diligent worker, diligent preparer, hard worker, talented young man," said Mornhinweg of Reynolds. "His skills have just gotten to a point where he can certainly help us."

In the grand scheme of the backup center competition, Reynolds has a few things working in his favor. For one, he's been learning the offense for the last three seasons and is more than familiar with the team's offensive philosophy and personnel. Second, Reynolds has center experience, having earned All-WAC honors during his senior season, when he played center exclusively.

"Each year that you're here, you get a little bit more confident in the system, you get better and better," Reynolds said. "You're always learning. You're always going to make some mistakes and that's why we have meetings and film, but I do feel confident and I feel comfortable getting in there with the other guys if I have to."

So does Reynolds feel the pressure to force his way onto the roster with no practice squad option to fall back on?

"A little bit," he said. "Obviously, you have to know that. But whatever happens happens. I just hope that I'm here."

If one player already penciled in for a backup role on the offensive line had to bet, Reynolds would be the odds-on favorite.

"That's probably be the toughest competition on the O-line, the backup center spot," said King Dunlap. "It's going to be tough to decide … but I think it'll probably end up being Dallas."

The Nerd

Julian Vandervelde's future at a position he's never played in a live football game is best summed up, of course, by the Eagles' legendary offensive line coach.

"We're going to make him play center," Howard Mudd said of Vandervelde.

And so the implementation has begun to turn Vandervelde, exclusively a guard since high school, into a starting-caliber center; but that will take some time. After taking some side reps as a center throughout the offseason and early in Training Camp, Vandervelde has seen his first live bullets at the position during two practices this week. The results thus far have been, well, mixed.

"He's unfamiliar with the position to say the least," said Kelce after Thursday's practice. "He's been doing a great job so far throughout Training Camp, but there were a couple things today where he's sliding, he's using his hands but he's not moving his feet. Center, you have to move your feet … so that you're always in position so that you can redirect and go back each way, and that's why usually centers are more athletic guys."

But those are technical glitches that Vandervelde can perfect in time. For now, Vandervelde's focus is on the radically different role he's expected to play at center from a mental standpoint.

"Right now, that's actually my primary focus, the cerebral side of it," said Vandervelde. "The physical part will come, that's why we're in camp, so we can drill the physical part in day after day after day. But the mental part of it is really something that you have to work on. It's vision, it's familiarity with defenses, familiarity with your offensive line, the couple of them you're playing next to. So that will come in time, I have no doubt about that, the physical part anyway. The mental part is kind of where I'm focused right now."

In actuality, because the center position is the most intellectual of the offensive line positions, it seems like a perfect fit for Vandervelde, a self-identified member of "nerd nation" who was a three-time academic All-American at Iowa while double majoring in English and Religious Studies (not to mention minoring in Japanese).

"As a guard, you listen to the center, you take your cues from the center," said Vandervelde. "As the center, you're the quarterback of the offensive line, you have to be the guy who sees the rotation of the safeties, who sees where the linebackers are moving and the patterns in defenses and how they're blitzing and you have to be able to make those adjustments on the fly, not just be listening for the adjustments from the center.

"I think that's why it feels more natural for me. My mind doesn't wander anywhere when I'm at center because it always needs to be focused on 50 different things at a time, and maybe it doesn't always have to be, but that's what it feels like because I'm just getting started here. It's not so automatic as guard was for me."

So what exactly goes through Vandervelde's mind after he breaks the huddle and approaches the ball at his new position?

"The first thing's the count," Vandervelde said. "You always have to have the count. We have a lot of different cadences, so it's definitely something that you need to keep track of. But outside of the cadences, you get up there, you look at the linebackers, you look at the defensive line, you look at the safeties, you have to pick up your (middle linebacker), remember your protection - that makes a big difference on where your ID'ing and which way the line is sliding, if you're sliding at all. Run, pass, every single aspect of it really does go through your head, step by step by step. And usually the last thing that goes through your head before you snap the ball is the snap count."

It certainly seems like Vandervelde is well-suited to handle the mental gymnastics of the position, but what about those physical questions asked by the job? Well, don't forget that Vandervelde, 6-2, 300, was actually selected one round ahead of Kelce by the Eagles last year. Of the main competitors for the backup center spot, Vandervelde has the highest pedigree, not only in draft status but in lineage as well.

As an Iowa offensive lineman, Vandervelde is among a long line of NFL Hawkeyes charged with protecting quarterbacks. The coaching he received in four years from Iowa head coach Kirk Ferentz, himself a former NFL offensive line coach, prepared Vandervelde well for life in the NFL. This offseason, knowing that center played a role in his future, Vandervelde took advantage of that Iowa community by picking the brain of 15-year NFL center Casey Wiegmann, another former Hawkeye, who has accrued 200 NFL starts.

That work ethic and thirst for knowledge are why Mudd believes Vandervelde has what it takes to handle the task at hand, even though he only appeared in one game as a rookie.  

"Vandervelde, before all of our games, he never dressed, and he was out there two hours before the game, some hours before the game, and he would rehearse his techniques for probably 45 minutes," Mudd recalled. "He would do some projecting and imagining and whatever that is, but he would do that before every game. In fact, one time I was sitting on the bench and Julian was right there in front of me doing a pass set and I said something like, 'You ended up leaning on your left leg, go do it again,' and he did. Because of that, I have a lot of trust and, I would say, expectation that he's going to step right in and he's going to be fine, I think. You're going to go out there and not even miss a beat. I believe we got what we drafted."

The Journeyman

Until Thursday afternoon, the entirety of Steve Vallos' 2012 Training Camp reps had come as the third-team center. This, despite the fact that Vallos is the only player on the roster other than Kelce who has started an NFL game at the position. A seventh-round pick of the Seattle Seahawks in 2007, Vallos first paid his dues on the practice squad his rookie season. Unlike Reynolds, Vallos then earned a bump up to the active roster, where he played all 32 games in 2008 and 2009, starting seven times at center and once at left guard. He then spent two seasons with the Cleveland Browns, playing in eight total games.

On top of that, Vallos set a Wake Forest record by starting 48 games during his collegiate career, during which he received first-team All-America honors from Sports Illustrated and The Sporting News. His experience as a starter then and during his brief time in Seattle still serves as motivation.

"It definitely helps," Vallos said. "A game is so different from practice and just the total mindset of it. It feels good to be the guy that's starting, your whole mentality changes. Experiencing that is good. It's harder to be back behind looking and learning rather than being up there with the first group and having everyone help you."

But despite that edge in experience, Vallos has not been discouraged by his current spot on the depth chart.

"You're able to get your work in," Vallos said. "You just want to get as many reps as you can and try and prove yourself however you can, whether it's with the three's or the two's. You just have to be ready. You never know what's going to happen. Training camp, guys get hurt, crazy things happen, so you just have to be ready whenever."

Just as predicted, Vallos was bumped up to second-team left guard on Thursday while Evan Mathis works his way back from an inner ear infection. Mathis creating an opening for Vallos is appropriate, because Mathis serves as a template for Vallos. Prior to falling into the starting left guard job for the Eagles last season (and subsequently earning a handsome long-term contract in the offseason), Mathis too was an NFL nomad, playing for three teams in six years, earning starts in only two of those seasons. It was two teams in five years for Vallos, counting his practice squad season, and two seasons of starting experience as well.

"He's somebody to look up to," Vallos said of Mathis. "He bounced around a lot and last year he had an unbelievable season and he benefitted a lot from it obviously this offseason. Obviously everyone wants to do that and not everyone gets that chance, but he really took advantage of the opportunity that he was given and that's something I would jump at the chance to do."

While Vallos does have the edge in experience over Reynolds and Vandervelde, he's the least familiar with the team's offensive scheme, though Vallos says he has played in similar schemes and is picking things up quickly. For now, Vallos' professional experience isn't just benefitting him, but the rookies playing alongside Vallos as well.

"It's pretty good because you go out there with confidence, you know this guy's going to go out there and make the right call for you to get going," said sixth-round pick Brandon Washington of Vallos. "It just feels good knowing his experience, because you can trust in his word and whatever he says, goes.

"Me being a rookie, I always felt like I was a professional at the college level, but now when I get in and I get around the vets like Steve, I can sit around and watch how he carries himself. That's a veteran right there. That's a guy who's been here before."

Part of the reason that Vallos is okay with working with the three's for now is that, because of his experience, the Eagles already have plenty of game tape on him. The Eagles obviously liked what they saw enough to bring Vallos on board, so there's comfort for the Wake Forest grad who, as a member of the ACC All-Academic Honor Roll, doesn't yield too much to Vandervelde in the intelligence department.

So how do the three main competitors stack up? There's actually an incremental increase in size from Vandervelde, 6-2, 300, to Vallos, 6-3, 310, to Reynolds, 6-4, 320. At 24, Vandervelde is the youngest, though despite his edge in game-time, Vallos, 28, is only four months older than Reynolds. But for a job as important as backing up Kelce, the decision won't be made on those metrics, but rather what happens on the field – especially in the preseason.

"I'm really excited about how this group is going to fall into place because we're going to be able, I said this during the last minicamp, I said that the group that we have, the 15 guys that we have, is the best group that maybe I've ever had," said Mudd. "Because even the guy that's supposedly the third-string guy, he can go into a preseason game and find out a lot about him. We need to do that. I think the preseason games ...  are really to train your backups, because when you need one, it's a big deal."

The Field

Did you think that was it? While Reynolds, Vandervelde and Vallos are the three primary options to serve as Kelce's backup, they're not the only options. First, there is always the possibility of a player shaking loose from final cuts whom the Eagles covet, a la Kyle DeVan last year. Internally, there's also Mike Gibson, who has been working exclusively as a second-team guard thus far. Gibson does have some limited experience at center.

"That's kind of what I'm known for is backing up both guards and center," Gibson said. "I did it in Seattle. I got a significant amount of starts at all positions. It's something I've had my eyes on since I got here and since (the Eagles) were looking for me."

And what about King Dunlap? After setting the NFL record for tallest player to start a game at guard last season, does Dunlap have his towering sights set on snapping the ball? Vandervelde mentioned it as a distinct possibility.

"That was a joke," Dunlap said. "That's a running joke."

Ok then. So then it is down to Reynolds, Vandervelde, Vallos, Gibson and, perhaps, a mystery roster cutdown casualty. Discounting the mystery player, Gibson feels comfortable in categorizing the other four as well-suited for the job.

"Center's definitely the most mental part of the offensive line," Gibson said, "that's why they give it to us smart people."

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