Stefen Wisniewski among those in camp competitions to watch

Stefen Wisniewski can play guard and be the backup center to Travis Kelce. Jeff Haynes/AP Images for Panini

PHILADELPHIA -- The Philadelphia Eagles host their draft picks and rookie free agents this weekend, the first camp in a series that will carry right into June.

No jobs are won or lost in these camps. That happens during training camp in August, with preseason games having a major influence. But we have a pretty good idea how the Eagles' roster looks going into the process, so it's a pretty good time to identify interesting camp battles.

Here are three starting spots that could be decided by competition this summer:

Left guard. In free agency, the Eagles signed former Houston Texans guard Brandon Brooks to a five-year, $40-million contract. They did that to fill the hole they had at right guard.

They did not make a similar move at left guard. The hope seems to be that one of several players can emerge as the solution to this problem area.

The leading candidate going into the May camps is Stefen Wisniewski, who signed a one-year contract late in free agency. Wisniewski played at Penn State and has been with the Oakland Raiders and Jacksonville Jaguars.

Wisniewski has primarily been a center in the NFL and has value as a guy who can back up Jason Kelce while also playing guard if needed.

A late addition to the competition is third-round draft choice Isaac Seumalo of Oregon State. Seumalo will get every opportunity to win the job, but may need a little experience before he is ready to start.

The in-house candidates are Allen Barbre, who started at left guard last year; Andrew Gardner; Malcolm Bunche, and Dennis Kelly.

Barbre's 2015 experience works for him and against him. He is familiar with line coach Jeff Stoutland's techniques and worked with left tackle Jason Peters. But the guard play overall was a problem for the Eagles last year and Barbre was in the middle of that.

Bunche was on the practice squad last year and should get a fresh look this summer. Gardner won the right guard job out of training camp, but wound up on injured reserve with a foot injury. Kelly has been a backup guard and tackle for the past several years.

Cornerback. Howie Roseman said that new defensive coordinator Jim Schwartz was eager to add as many cornerbacks as possible during the offseason. The Eagles also traded away Byron Maxwell, one of their starters from last year.

Eric Rowe, last year's second-round draft pick, showed promise in a starting role late last season. Rowe had to play after starter Nolan Carroll broke a bone in his lower leg.

Carroll is back with the team this year and will compete for a starting spot. So will Leodis McKelvin and Ron Brooks, two former Buffalo Bills who are familiar with Schwartz's defense.

Schwartz will also take a look at Denzel Rice, JaCorey Shepherd and Randall Evans, who were all rookies last year. Shepherd spent the season on IR with a torn ACL. Former CFL standout Aaron Grymes is also in the mix.

Bottom line: Rowe is likely to start on one side, but both outside jobs and the nickel corner spot are basically up for grabs.

Defensive end. This is an unusual situation. While switching from a 3-4 scheme to Schwartz's 4-3 defense, the Eagles basically moved ends (Fletcher Cox) to defensive tackle and moved outside linebackers to defensive end.

That logical assumptions is that Brandon Graham and Connor Barwin will be the starting defensive ends. But don't forget Vinny Curry. He was not an ideal fit in the 3-4 scheme, but was still a capable pass rusher under Bill Davis.

The Eagles thought enough of Curry to give him a new five-year, $47.5 million contract with $23 million guaranteed. That means he is the highest paid defensive end on the roster, so Curry is likely going to start.

Schwartz's scheme relies on pressuring quarterbacks and he is likely to rotate players in order to keep fresh legs in the game. So it may not matter that much whether Graham or Barwin starts games. Both will be on the field a lot. And Schwartz could use either or both as standup rushers on the outside, which could mean they sometimes drop into coverage.

In short, the competition is for starting jobs, but also for customized roles in Schwartz's scheme.