Chip Kelly's arrival in Philadelphia has meant that the Eagles have started on the road toward to an eventual transition to the a 3-4 defense. Kelly said that this was his preferred front, but also admitted that it's not something that can be forced in one year.
Making a major transition in defense, if done right, is best implemented as you get the players able to do it. For the Eagles, that means finding a bigger "thumper" type middle linebacker, a space eating nose tackle, probably another 5 tech DE/DT, and a SAM.
And this is all while still having to almost completely rebuild the secondary. Suffice to say, it will take time. However, time isn't necessarily something NFL coaches have. Chip Kelly certainly has a couple years to put his plan in place, but the reality is that if he doesn't have this team in playoff contention in two years, questions will start arise. If 3 years go by, he's officially "on the hot seat."
We see this play out every year with coaches. So while Chip may be wise to say he plans to ease the 3-4 defense in, he's probably only talking about a year or so.
So where does the personnel come from? Obviously first and foremost players need to be developed through the draft. However, if he wants to get his defense a head start, he could also dip into the free agent market to find players to fit the system.
Two such players just hit the market after being cut by the cap strapped Jets. ILB Bart Scott and OLB Calvin Pace. Scott isn't really much bigger than DeMeco Ryans, but he's got a career's worth of experience manning the middle in the 3-4 and has thrived as a run stopper in that role. Plus, he'd bring an attitude to the center of the Eagles defense that probably hasn't existed since Jeremiah Trotter was there (CAN'T WAIT!).
Calvin Pace has never been a star, but has been a good 2 way OLB in a 3-4 for a long time. He's good against the run and a capable pass rusher. Both players were cut due to cap concerns and could potentially be had on the cheap.
Question is whether they would be worth pursing. Both guys are 32, so they can still contribute but are at the tail end of their careers. Not exactly the type you would think to target for a rebuilding team. I'd personally pass on Pace because I think the Eagles have several guys who could potentially fill that role, but I love Bart Scott. I'd love that attitude and leadership and I think he could really help set a tone here.
The Eagles won't do it, but I think at some point they need a find a leader. And not a "lead by example" guy. Someone needs to stand up and make people accountable on that defense. Maybe to get that, you need to grab a veteran even if he may not be around when the rebuild is truly complete.