Could Eagles run a 3-4 defense?

Jeff McLane of the Philadelphia Inquirer has a lot of good background information on the Philadelphia Eagles' hiring of Chip Kelly as their new head coach, including this:

Kelly favors an aggressive, attacking-style defense and will likely change the Eagles' scheme from a 4-3 to a 3-4, a source familiar with the coach's thinking said.

Well, that's interesting, no? And the way the Eagles played defense this year, it's hard to argue against change, even if it's for change's sake. But my first reaction is that I don't think the Eagles have the personnel to make this switch, and that it would require an even more drastic defensive rebuild than the one that faces them now.

Right now, they need to fix the secondary, but they have an excellent, deep, athletic 4-3 defensive line as well as a couple of good linebackers in DeMeco Ryans and Mychal Kendricks. If they switch to a 3-4, they need to evaluate what they have at all three levels of the defense, and here's what I think they'd find at the first two:

Defensive line: It's easy to see Fletcher Cox and Cullen Jenkins as good 3-4 defensive ends, but the Eagles would need a nose tackle. It's possible Antonio Dixon could be that, or they could draft Utah's Star Lotulelei with the No. 4 pick, but it would become a significant area of need if the Eagles did in fact make the switch.

Linebackers: Personally, I like the idea of Brandon Graham as a stand-up outside linebacker and I think Kendricks fits the mold of a fly-around inside linebacker in a 3-4, assuming he develops some. But I don't see Trent Cole making the transition to stand-up outside linebacker very smoothly. And Ryans, who was Philly's best defensive player in 2012, was just traded from Houston a year ago because he didn't fit anymore after the Texans switched to a 3-4, and the Eagles saw him as a prototypical middle linebacker in a 4-3.

The problem here, as Matt Williamson of Scouts Inc. said when I asked him about this, is that a switch to a 3-4 doesn't really benefit any of the Eagles' current defensive players. Sure, some of them (such as Cox and Graham) could make transitions, but it's hard to see how any of them would thrive as a result of the change. And if that's the case, that means the Eagles are going to spend this offseason and likely the next one trying to figure out which pieces fit and which spots require them to find replacements. Seems like a major project that would require time and patience, and that's not always something NFL fans and franchises are willing or able to offer.

Who will run the Eagles' D? NFL Network raised the names of Georgia's Todd Grantham and Florida's Dan Quinn as potential defensive coordinators under Kelly, and Adam Schefter says he's heard both as possibilities. Whoever it is will have a significant responsibility to rescue a defense that flopped more or less completely in 2012, and his ability to do that will go a long way toward determining whether Kelly's tenure in Philadelphia is a success.