The Bills are going to use more 3-4 packages in what defensive coordinator Mike Pettine told buffalobills.com will be a "multiple front, multiple coverage defense," but the team needs to find the right pieces if it wants to make a successful switch.
Along the defensive line, Buffalo has a formidable front consisting of Kyle Williams and Marcell Dareus. Williams will likely play the nose, and the defensive end spot opposite Dareus could come down to a number of Bills in training camp.
The team will have its biggest issues trying to find capable linebackers to play in the new 3-4 front. Marquee player Mario Williams' best fit is as a 4-3 defensive end, and while he can make an impact as a 3-4 pass-rusher, he's not the same player there as he is with his hand in the dirt.
Buffalo needs to build this defense up the middle, and with both Kyle Williams and safety Jairus Byrd (who received the franchise tag on Monday) in place, general manager Buddy Nix needs to do his best job to go after an inside linebacker.
Ravens linebacker Dannell Ellerbe would be a great fit, according to Gary Horton and Field Yates of ESPN. Ellerbe filled in admirably for the Super Bowl-bound Ravens last season when Ray Lewis went down. He'd be a perfect fit in Buffalo.
According to the report, Ellerbe is a three-down player and could be a young building block for Buffalo. Baltimore may not be able to retain Ellerbe, Joe Flacco and Paul Kruger all in one offseason. The team could elect to let the inside linebacker go.
Should the Bills find a way to maneuver the hard hitter to Buffalo, it'd almost certainly lock them into picking an offensive player with the eighth overall pick. Any position from quarterback to wide receiver to offensive tackle is a distinct possibility there.
A defense with Kyle Williams, Dareus, Mario Williams, Ellerbe, Byrd and a more mature Stephon Gilmore could be the ingredient for Pettine's recipe for success.
Pettine will want to mix up his blitz packages. Ellerbe will be able to manage on-field play-calling, after sitting behind Lewis in Baltimore and watching players like Terrell Suggs and Paul Kruger have a huge impact as blitzers in an attacking 3-4 scheme.
Ellerbe's best attribute is his ability to stuff the run, but he's not a bad pass-rusher in his own right. He actually racked up 4.5 sacks in 2012 and could build on that total in an expanded role.
Pettine will have to be careful, however, as Ellerbe is limited in his ability to cover receivers. He won't be asked to shut down Rob Gronkowski if given an opportunity with Buffalo.
Look for the Bills to be aggressive in their pursuit of this inside linebacker. The team is committed to improving defensively after hiring a new coordinator on that side of the ball and eschewing a contract extension for Andy Levitre to give Byrd the franchise tag.
Dannell Ellerbe would represent significant improvement.