If Demetress Bell proves to be a good replacement at left tackle, the Eagles could have one of the best offensive lines in the NFL. The other four spots all feature returning starters and the group was very good for parts of 2011. It doesn't hurt to have Howard Mudd as the coach who is running the show. He is one of the great line coaches in the history of the league.

Life sounds pretty good, huh?

There is one concern - depth. While the starters should be outstanding, depth is a major question. King Dunlap has proven to be a good backup over the years. He has started at left tackle, right tackle, and even played some guard. Dunlap is slated to be the top backup again in 2012. He still has to earn a roster spot, but so far in camp has played well in both team sessions and individual drills. I'm surprised no team took a chance at signing Dunlap and seeing if he could possibly succeed as a starter. While he's not a great player, Dunlap has been solid in his role for the Eagles.

Rookie Dennis Kelly was drafted in the fifth round. He played left tackle at Purdue. The Eagles have lined him up all over the place. Right now he is the right tackle on the number two offense. He's gotten snaps on the left side and at guard. Kelly is getting mixed into things pretty aggressively, but he's got a long way to go. He has struggled when facing Brandon Graham either in team sessions or individual drills. Graham is fast off the ball and stays very low. Kelly is a tall player with long legs. Getting low to block ends is something he's still adjusting to.

I think Kelly has shown enough potential that he will make the team. The Eagles feel that he can be a left tackle in the future. He has good feet, but must play with better pad level. He's still adjusting to the speed of the game at the NFL level, but I like the fact that he doesn't look overwhelmed even when he does get beat. That happens to most rookies. Not all handle it the right way. I don't think he'll play much this year, but preseason games will give us a much better idea of exactly where he is in terms of development.

The other backup tackles are D.J. Jones and Thomas Welch. I thought Jones would push for a roster spot, but he's running with the third team and hasn't stood out much when I've watched him. Welch is a developmental guy. He has good size and some ability, but is a limited player. Welch has to sell out to block edge rushers. This leaves him vulnerable to inside moves. Phillip Hunt beat him with an inside move on Thursday and barely got touched. Not good. That did happen in a one-on-one drill, not a place where he will shine. Welch is better in a team setting. He gets the benefit of the snap count. The play might be run or pass. Welch gets in a good stance, plays with good pad level, and is technically proficient. He just lacks the foot speed and agility to handle speedy edge rushers.

Julian Vandervelde is entering his second season and has a chance to be the top backup on the interior. The Eagles used him at guard last year, his natural position. He is getting mixed in at center this summer. The results have been mixed so far. Vandervelde has the athleticism to play center. He's got one main obstacle - snapping the ball. He's inconsistent with that and clearly you can't have that. The quarterback-center exchange is the first key to any offensive play. Vandervelde is working on his snapping, but it does take time. At the very least, the Eagles do like him as a guard. He might be a self-proclaimed nerd off the field, but he's a tough guy on it. He is short, but uses that to his advantage and plays with good leverage. He moves well enough to be a good blocker on the second level or out in space.

Dallas Reynolds is a name that not many people figured would be the focus of any training camp talk. Right now Reynolds is the primary backup center. On Thursday he took snaps at left guard with the starters when Evan Mathis was down. Wow. Didn't see that coming. Reynolds looks to be in good shape. He was 320 pounds in the past, but appears lighter, as Mudd prefers his linemen that way. Reynolds played guard, tackle, and center in his career at BYU. He spent the past three years on the Eagles practice squad. Don't undersell that fact.

The Eagles kept him around for three years not because he was the most talented guy. If he was, someone would have picked him up by now. Staying that long shows that he is tough, coachable, and that he is the kind of player the Eagles like to keep around. Reynolds is never going to be a great athlete. He is quick from snap to block, which is important at center. He doesn't have quick feet, though. That hurts him on reach blocks, which are a big part of the Mudd scheme. Reynolds can anchor when he stays low and gets his feet set. There have been some plays where Antonio Dixon was able to drive him back, others where Reynolds won.

I don't know how much the Eagles like Reynolds, but the fact they have him as the backup center and also gave him snaps with the starters at guard tells you they want to see what he can do. Preseason games will likely be critical for him. Reynolds has been solid in camp, but hasn't played so well that it blew you away. Also, he's 28 years old so it isn't as if he is a young player still in the developmental stages. I think Reynolds has a legit shot to make the team, but he isn't on safe ground yet.

Mike Gibson was signed as a free agent this offseason. The Eagles drafted him originally, but then Gibson went to Seattle for a couple of years. He has the build and athletic ability to be a good fit in Mudd's system. He has played just guard so far, but there was talk at one point of letting him play some center. Gibson has some starting experience and that helps his cause to be one of the backups. He's looked solid in camp.

Steve Vallos is another veteran that the Eagles added in the offseason. I haven't paid as much attention to him. Like Gibson, he's got the size and skill set to fit Mudd's system. Vallos played guard, tackle, and center while at Wake Forest. Heck, he even played center in the East-West Shrine Game and looked good. A lot of NFL teams felt his future was at center. A lot of time has passed since then, but Vallos does at least have starting experience at center in his background. He's mainly been a guard in the NFL.

One thing to keep in mind with guys like Gibson and Vallos is that they are new to Mudd's scheme and style of blocking. They might have needed the first week of camp to get the hang of things. The next week or so could be when the light goes on for them and they start to play better.

Rookie Brandon Washington is battling for a roster spot. He is a pure guard. He did play some tackle in college, but has no shot to play there in the NFL. Washington could be an ideal practice squad candidate. Give him a year to get in top shape and adjust to the NFL, as well as learning the Mudd system. If the Eagles see enough potential in Washington, they may not want to risk trying to put him on the practice squad. So far he's been okay in camp, but hasn't stood out to me. I think of him more as a project, but we don't know how Howard Mudd feels and he has the key vote.

Alfred McCullough is another rookie at camp. I think he is the longest of the long shots.

Ideally, the starters will stay pretty healthy. Dunlap will fill in for a game or two as needed. Either Vandervelde or Reynolds will prove to be an effective backup. Kelly will spent the year on the roster, but inactive for games. He can focus on developing for the future. Washington will be either on the team or practice squad and can also focus on the future.

A rash of injuries would be problematic, but that is true for most teams. The Eagles have three tackles they like in Bell, Herremans, and Dunlap. Some teams don't even have a pair of starters they trust. The interior spots are more of a question. Mudd has shown the ability to develop players over the years so I trust that he'll figure something out. The names might not be flashy, but the cupboard isn't bare...just unproven. Trust in Mudd. If you start to get nervous, think back to the days of Nick Cole and Max Jean-Gilles. That should make the 2012 group look a lot better.