CHIP KELLY says his depth chart is written in sand, which doesn't mean he takes notes on an Etch A Sketch.

It's his clever way of saying that there is precious little permanence on his roster this early in a training camp in which he has posted a "Help Wanted" sign on every job but pastry chef in the NovaCare cafeteria.

At the moment, with the Sept. 9 season opener against the Redskins still 5 1/2 weeks away, it's safe to say no more than nine or 10 of the Eagles' 22 starting jobs are completely locked up.

Running back LeSean McCoy and wide receiver DeSean Jackson can breathe easy. So can offensive linemen Jason Peters, Evan Mathis, Jason Kelce and Todd Herremans, and probably first-round right tackle Lane Johnson.

On defense, the only players who can go to sleep at night knowing they definitely will be in the starting lineup against the Redskins next month are linebackers Connor Barwin and DeMeco Ryans and defensive lineman Fletcher Cox.

After giving up a league-high 33 touchdown passes last season, the Eagles gave the heave-ho to both of their starting corners, Nnamdi Asomugha and Dominique Rodgers-Cromartie, and signed free agents Cary Williams (Ravens) and Bradley Fletcher (Rams).

The assumption has been that Williams and Fletcher will be the season-opening starters, and maybe that assumption will end up being correct. But Brandon Boykin is determined to have something to say about that.

Boykin, a 2012 fourth-round pick who was the team's nickel corner as a rookie, has been one of the most impressive players in training camp so far. He's been all over the field making plays, both in one-on-one drills and team work.

"I'm taking reps at nickel and outside, whether it's 'ones' or 'twos,' trying to get as many as I can," Boykin said. "In this defense, we go so fast. Everybody's got to be ready to play every position. Because somebody might get tired, and you have to be the next man up.

"I know I can play outside. I know the coaches know I can play outside. I have the confidence once I get that chance."

Boykin's biggest hurdle in the way of winning a job on the outside is one he can do nothing about: his size.

He's just 5-9 in an era when defensive coordinators prefer longer corners who can match up with the plethora of big, strong wideouts.

The departed Asomugha is 6-3 and Rodgers-Cromartie 6-2. Williams is 6-1. Fletcher is 6-foot. Not so long ago, you could count the number of corners who were 6-1 or taller on your fingers.

Even with 4.4 speed and an impressive, 41-inch vertical leap, people still have reservations about Boykin's ability to cover bigger wideouts on the outside.

"It's yet to be determined," defensive coordinator Bill Davis said. "There have been a lot of shorter corners out there that have held up [on the outside]. But it is a challenge.

"Being around Larry Fitzgerald [who is 6-3 and 225 pounds] out in Arizona for a few years, you put a shorter corner on him and he goes and runs the fade in the red zone. Every game he had two or three of them.

"There are challenges on the outside when you're not the biggest guy against the bigger receivers. It's not that it can't be done. But you've got to prove that you can do it out there. The fit right now is a little easier for him at nickel. But we're not eliminating the corner position for him either. We'll evaluate that as we go."

Despite the Eagles' horrendous overall numbers against the pass last season, Boykin did a very credible job inside in his first NFL season.

He was on the field for 526 defensive plays, which was 52.9 percent of the team's defensive snaps. The only Eagles rookie who played more snaps than Boykin last year was fifth-round offensive tackle Dennis Kelly (703). First-round defensive tackle Fletcher Cox also played 526 snaps.

Boykin was targeted 50 times and gave up just 27 completions (54.0) and three touchdowns.

According to Pro Football Focus, just 19 corners who played at least 500 snaps last season had a better completion-percentage-against than Boykin. Fifteen of those 19 started eight or more games.

The only nickel corners with a better completion-percentage-against than Boykin were the Packers' Casey Hayward (44.6), the Broncos' Tony Carter (49.2), the 49ers' Chris Culliver (49.3) and the Patriots' Alfonzo Dennard (50.8). And Carter, Culliver and Dennard all gave up more touchdowns (four) than Boykin.

Boykin said he has no fear of going against the Goliath wideouts. "Call as many jump balls as you want," he said. "I'm gonna go get it."

Williams started 16 games for the Ravens last season but gave up a team-high six touchdown passes. The Eagles still gave him a 3-year, $17 million contract with $10.5 million of it guaranteed.

Assuming he gets over the hamstring strain that has kept him out of the most of the first 4 days of practice and can stay on the field, he'll probably have to stink up NovaCare pretty badly in the next month not to be one of the team's two season-opening starting corners.

But Fletcher is another story. He received a modest 2-year deal with just $2.35 million guaranteed money. He's been hurt a lot in his first four seasons and has played more than 400 snaps and started more than four games just once in those 4 years. That was in 2010 when he played 1,004 snaps in 15 starts. He played just 247 snaps last season.

Truth is, Davis and Kelly probably would prefer to leave Boykin inside because, other than seventh-round rookie Jordan Poyer, they don't have many other inside options.

"Brandon is explosive," Kelly said. "I'm pleased with where he is so far."

The Eagles had just eight interceptions last season. Only the Cowboys and Chiefs had fewer (seven). They had four picks in their Week 1 win over Brandon Weeden and the Browns, then just four more in the next 15 games. At one point, they went eight games in a row without an interception.

"That was just unbelievable," said Boykin, who had no interceptions. "It's something we can learn from as players, just expecting more out of ourselves and taking it to another level.

"It was a journey for me, just being a rookie and trying to get adjusted to being in the NFL. Then we had the challenge of changing coordinators and a lot of other things going on.

"It taught me how to handle adversity early in my career. So I don't think it could get much worse than what happened [last year]. I think I'll be ready for anything."

Boykin was in a sporting-goods store back home in Georgia during the bye week last October when he found out defensive coordinator Juan Castillo had been fired and replaced by secondary coach Todd Bowles.

"I was buying some stuff and looked up at the TV in the store and saw the news," he said. "We knew right then it would be different and we were going to have to pick up the slack. It wasn't the coaches. We were the ones out there playing. But it didn't happen."

Boykin is hopeful the new, more aggressive defensive scheme will translate to more interceptions.

"It's a playmaking defense," he said. "It puts us in a position to make a lot of plays. Not as much read-and-react. With the pass rush and with us being [more] aggressive with our coverage, it's going to give us more opportunities for turnovers that we didn't have last year."

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