Complete Philadelphia Eagles Training Camp Preview

Philadelphia Eagles training camp is finally upon us. Players report to the NovaCare Complex on Saturday and practice kicks off Sunday, when the march to the 2015 NFL season will have begun in earnest.

With camp about to get underway, it gives us one final chance to review all of the major storylines heading into the franchise's 83rd campaign. Each offensive and defensive unit is featured here as we touch on all of the changes and position battles ahead this summer, with some thoughts on what to expect by the time the Eagles' season opens on Sept. 14.

Get ready—football is finally back in Philadelphia.

There Is a Quarterback Competition (Sort Of)

Matt Rourke/Associated Press

Since his arrival, the expectation has been Sam Bradford will be under center for the Eagles on Week 1, and no doubt that's the plan. However, head coach Chip Kelly has no intention of simply handing over the job.

The Eagles may have traded Nick Foles and draft compensation for Bradford, who also happens to be making almost $13 million in 2015, according to Spotrac. Yet he's also coming off back-to-back torn ACLs a mere 11 months apart and hasn't played in an NFL game in nearly two years.

If Bradford experiences a setback or simply looks rusty, that's an in for Mark Sanchez, now in his second season with the Eagles. The best quarterback will play, period, and Sanchez is healthy and comfortable with the system.

Ultimately, the job is more Bradford's to lose than Sanchez's to win—but that is a distinct possibility.

The Rebuilt Secondary

David Zalubowski/Associated Press

By far, one of the biggest issues in Philadelphia has been atrocious pass defense, but no more. Or at least the Eagles are hoping they've fixed the glaring weakness that was their secondary. The organization invested plenty of resources into its defensive backfield during the offseason, and while the depth chart has yet to be sorted out, the unit definitely stands to be improved.

The key addition is cornerback Byron Maxwell. Signed to a big-money contract as a free agent from the Seattle Seahawks, the Eagles immediately installed Maxwell as their No. 1 corner and expect him to lock down one half of the field at least.

At present time, fellow free-agent addition Walter Thurmond has been reunited with Maxwell, a teammate in Seattle, and is the front-runner to start at safety alongside incumbent Malcolm Jenkins. Thurmond has never played safety, either in college or professionally, but the Eagles are not exactly deep there, so the hope is he at least provides stability for the back end of the secondary.

In addition to free agency, the Eagles spent three draft picks on defensive backs, including a second-round selection on Eric Rowe out of Utah. Rowe is expected to compete with veterans Nolan Carroll and Brandon Boykin for the starting cornerback job opposite Maxwell.

There's certainly a lot more talent in the secondary overall, which is a plus. Now the Eagles must put the pieces together and plug that leak for good.

An Arsenal on Offense

Matt Slocum/Associated Press

The Eagles may have traded All-Pro running back LeSean McCoy and lost Pro Bowl wide receiver Jeremy Maclin in free agency. But believe it or not, there is no shortage of weapons in Philadelphia's offense.

First, the club replaced McCoy by signing Ryan Mathews and reigning NFL rushing champion DeMarco Murray to free-agent deals. Obviously, Murray demonstrated the type of workhorse he can be for the Dallas Cowboys last season, but Mathews is underrated, having rushed for 1,000 yards twice in his career with the San Diego Chargers. They join Darren Sproles to form hands down the best fleet of backs in the league.

Then came the draft, where the Eagles used the 20th overall selection on Nelson Agholor out of USC. Agholor was one of the most productive receivers in college football last season, finishing top 10 in the nation in receptions (seventh), yards (ninth) and touchdowns (tied for 7th), and enters his rookie season amid high expectations—perhaps even a shot to be Offensive Rookie of the Year.

Agholor joins a young, up-and-coming receiving corps that includes 2014 second- and third-round picks Jordan Matthews and Josh Huff, as well as 2013 second-rounder Zach Ertz at tight end. Matthews and Ertz in particular appeared to be on the verge of Pro Bowl-caliber production themselves last season.

With veterans Riley Cooper, Miles Austin and Brent Celek to assist in the aerial assault, there are plenty of quality targets. The only question is: Are there enough footballs to go around?

Same Dominant Front Seven—Plus Alonso

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Philadelphia easily fielded one of if not the very best defensive front seven in the entire NFL in 2014. The Eagles limited ball-carriers to just 3.7 yards per carry last season, which tied for fourth in the league, but were a terror to opposing quarterbacks as well, finishing tied for second with 49 sacks.

Little has changed. Brandon Graham, 27, replaces 32-year-old Trent Cole opposite freshly minted Pro Bowler Connor Barwin at outside linebacker, which is likely an upgrade if there's any difference at all. Oh, and the Eagles also received Kiko Alonso in that McCoy trade we mentioned earlier, further bolstering the interior of the linebacking corps.

Alonso has the potential to be a three-down beast for the Eagles, just as he was in his first NFL season with the Buffalo Bills. In 2013, Alonso racked up quite the line on his way to PFWA Defensive Rookie of the Year honors—159 tackles (third in the league), two sacks, four pass breakups, four interceptions and a forced fumble.

Alonso is coming off of a torn ACL that erased his 2014 campaign, but at worst he's dropped in a rotation with DeMeco Ryans and Mychal Kendricks. With a dominant front of Fletcher Cox, Bennie Logan, Cedric Thornton and Vinny Curry building the wall in front of them, the linebackers should feast.

Shuffling the Offensive Line

Tony Gutierrez/Associated Press

The good news is the Eagles have strong foundational pieces along the offensive line. Left tackle Jason Peters is coming off of his seventh Pro Bowl and remains one of the most dominant linemen in the NFL, Jason Kelce is fresh off of his first invite to the Pro Bowl and calls the shots, while 2013 first-round pick Lane Johnson is emerging as a force to be reckoned with at right tackle.

Then again, all three of those guys are going to be playing next to somebody new this season. That's because the Eagles are replacing not one but both offensive guards—and are attempting to do so largely from their own depth.

Journeyman Allen Barbre is expected to fill in at left guard, and the Eagles claim they are comfortable with this, even though he's started as many games in the NFL as years he's been hanging around the league (eight).

Right guard is currently a bit more open to competition. Matt Tobin and Andrew Gardner saw some time there last season, with Gardner eventually taking over to finish out the season. The Eagles also recently signed former third-round draft pick John Moffitt out of early retirement to push for the vacancy.

It will be an interesting experiment to say the least. The Eagles haven't invested a draft pick in their offensive line since Johnson, leaving journeymen and undrafted-developmental types to plug into the openings. It seems risky, to say the least.