"I think it gives us a lot more versatility, and I think it causes a lot of problems defensively because you don't know exactly where that fourth [pass] rusher is coming from," Kelly said. "But will we be able to get to the total package?"
Probably not if Cole and Graham are the best options opposite linebacker Connor Barwin. More than likely, the Eagles will land somewhere in the middle - which would be a hybrid, more specifically the 4-3 "under," the scheme Davis ran when he was defensive coordinator of the Cardinals.
But make no mistake; the Eagles are not going back to the one-gap 4-3 "over." Kelly and the Eagles spent significantly in the offseason to acquire pieces to fill the traditional space-filling roles - a nose tackle and two-gap defensive ends - in a 3-4.
"We feel like we're a little bit stouter inside than when I first got here in January," Kelly said.
But other than acquiring Barwin through free agency, the Eagles did little to add 3-4 outside linebackers. Kelly's hands were tied to an extent. Cole's large contract made it nearly impossible for the Eagles to move the longtime end, and Graham, who showed promise as an edge rusher last season, was the team's top draft pick in 2010.
And after the top three there is little depth with Phillip Hunt, another converted end, Chris McCoy, and Everette Brown.
"We haven't been drafting for this and [we're] converting some of those defensive ends to see what they can do," Kelly said. "But our job is to do a great job of figuring out what they do best and then playing to those strengths."
It may be early in the evaluation period, but if the spring and Friday's first full squad practice revealed anything about the conversion, it is that Cole and Graham may never be able to drop effectively. Barwin is clearly ahead of both.
"I think Trent did a nice job today," Kelly said. "It's a transition for Trent. It's a transition for Brandon."
But will they ever be able to fully make the transition? Kelly and Davis have six weeks until the opener, but a decision will have to come much earlier.
"Shoot, by the third week, boy, if you ain't got it, you just ain't got it," Graham said.
And if Cole and Graham don't get it by then, Davis will have to draw up a defense that caters to their skills. And the most obvious would be his 4-3 "under." In that scheme there are two outside linebackers - one on the strong-side (over the tight end) that drops the most (Barwin) and another - the "Predator" - (Cole or Graham) that rushes the passer 90 percent of the time.
The Predator lines up in a three-point stance most of the time, thus giving the front a 4-3 look on base downs.
"I don't know what I'm playing yet," Cole said. "I don't know if I'm playing D-line or linebacker but I'm practicing at both, so we'll see."
Cole and Graham each shed about ten pounds during the offseason. Both said they weigh 264. But it's not just their bodies they had to change. Cole and Graham have, for the great majority of their careers, rushed from four- and three-point stances with one primary goal: getting after the quarterback.
Graham said rushing from a stand-up position was no different.
"You tend to have the same burst as you would when you're coming out of a three-point stance," he said.
But dropping into coverage is something else altogether. One-on-one receiving drills typically favor the offense, but Cole and Graham struggled to keep up with tight ends on Friday.
"It's frustrating sometimes because you know, man, I'm good and you just got to keep playing that in your head," Graham said. "When one-on-ones come, somebody is going to beat you and you just got to come back the next play and just keep competing."
As Kelly has said when talking about the quarterback competition, the players will decide who wins. In this case, the outside linebackers will ultimately decide the Eagles' defensive scheme up front.
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Contact Jeff McLane at firstname.lastname@example.org. Follow on Twitter @Jeff_McLane.