IN JUST 6 WEEKS, the Eagles will open the 2013 season in Washington against the Redskins.

At the moment, they don't know who their starting quarterback will be in that game, and they also don't know exactly what kind of defensive alignment they will be using.

Neither of those things is a cause for concern at the moment. Chip Kelly is letting Michael Vick and Nick Foles duke it out for the starting-QB job and one of them eventually will be declared the winner.

As for the defense, well, Kelly's coordinator, Bill Davis, knows the scheme he wants to play. He's just not sure yet he has all of the pieces to play it.

The plan is for the Eagles, who played a wide-nine 4-3 the last two seasons, to switch to a two-gap 3-4.

That's a major transformation. To do it, you need to get bigger, much bigger, up front, and you need pass-rushing outside linebackers who also can drop into coverage when necessary.

Davis and Kelly think they're OK up front. They signed veteran defensive lineman Isaac Sopoaga during free agency, traded for 6-8, 340-pound behemoth Clifton Geathers, and used three of their eight April draft picks on defensive linemen with 3-4 backgrounds (Bennie Logan, Joe Kruger, David King).

They also have several holdovers from the Reid regime who should be able to make a fairly smooth transition to a 3-4, including 2012 first-rounder Fletcher Cox, Antonio Dixon and Cedric Thornton.

The key to this scheme-change operation, as Kelly pointed out Friday, will be ends-turned-linebackers Trent Cole and Brandon Graham.

The Eagles brought in one proven 3-4 outside 'backer in March when they signed Connor Barwin. But they need Cole or Graham, or ideally, both, to prove they can make the switch from a hand-on-the-ground end to a standup linebacker.

"We're going from a wide-nine to a 3-4," Kelly said after the Eagles' first full-squad training-camp workout. "When do we get to a 3-4? I don't know. We may have to stop at being a one-gap [4-3] over/under defense depending on [if they are] still making an evaluation of what our guys can do.

"We haven't been drafting for this. We're converting some of the defensive ends [Cole, Graham and Phillip Hunt] to see what they can do. Our job is to see what they do best and play to those strengths. Where we land on that realm, I can't exactly tell you until we get a chance to see those guys."

Cole, 30, is a two-time Pro Bowler who has notched nine or more sacks in five of the last six seasons. Graham, the Eagles' 2010 first-round pick, was one of the defense's few bright spots last season, recording a team-high 5 1/2 sacks and 31 hurries in just 220 pass-rush opportunities.

But it remains to be seen whether either of them can rush the passer as effectively from a standup position as they did from a three-point stance. An even bigger question is whether they can drop back and cover.

"It's a transition for Trent," Kelly said. "It's a transition for Brandon. It's a transition for Phillip. We're conscious of that. We know it's not something they're going to pick up just like that, because they've never been asked to do it.

"Brandon dropped [into coverage] a little in college. Trent dropped a little bit when Sean McDermott was here. But that was a long time ago.

"If you're a good teacher, you don't get frustrated early. If people could pick it up like that, then everybody would do it. But it's not. It's a hard transition. But we believe it's the best thing for us.

"It gives us a lot more versatility and causes a lot of problems defensively because you don't know where that fourth [pass-rush] pressure is coming from."

Cole and Graham wouldn't necessarily be used a lot in coverage. The 49ers' Aldon Smith played 1,223 snaps last season and dropped into coverage a total of 111 times, according to The Cowboys' DeMarcus Ware played 896 snaps and dropped just 64 times. Barwin played 1,137 snaps for Houston and dropped just 101 times.

"At the end of the day, I'm not going to ask a guy to do something he's not good at," Davis said. "A guy like Trent, we know he's a physical player, great against the run, relentless in his pass rush. He's had some great 10-sack seasons here. I want him to do 10-plus. In order to do that, he's got to be coming forward."

Cole said he thinks he'll be an even more effective pass rusher as a 3-4 linebacker than he was as a 4-3 end.

"I'm used to getting double-teamed a lot," he said. "Now I'm wide-open. Ain't nobody going to be outside of me. I'm just going to be barreling in with a running start.

"I just love the fact that I'm wide-open and can do whatever the heck I want to do when I'm supposed to go on the rush. And if I have to contain [against the run], that will be easy. I'm excited to get a chance to do that."

Asked about his coverage skills, Cole said, "If you've got it, you've got it. If you're athletic enough to do it, you'll be able to do it."

Graham, who played at 275 pounds last season in the wide-nine, reported to training camp at 264. He hopes to get down to 260 by the first preseason game.

"They told me to be the 260s when I came back [from vacation]," Graham said. "I wanted to get into the 250s. But that ain't happening just yet."

Graham said he knows that he and Cole are the keys to the switch to a 3-4.

"I definitely feel the spotlight on us as far as how this defense comes together," he said. "I just want to hold up my end of the bargain so coach doesn't have to bring somebody else in and can trust us to be out there."

Both Cole and Graham had their ups and downs in coverage at yesterday's practice. There likely will be a lot of days like that.

"By the third week, if you don't got it, you just don't got it," Graham said. "Sometimes things don't come together as quick as you want. But I think the way we're working, the sky's the limit for us.

"I wasn't too frustrated [yesterday] because coach was happy with how physical we were with [the receivers]. But sometimes, you don't have to be as physical. You have to mirror them and stay in front of them."

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