The wave of uncertainty hit Buffalo Bills fans when Chan Gailey hired Dave Wannstedt to his defensive staff this off-season. Adding to the fog was the retention of George Edwards as the team's defensive coordinator. Buffalo intended to play a 3-4 defense heading into 2010. They played a lot of 4-3 during the 2010 season due to personnel issues. Edwards has coached both, while Wannstedt coached 4-3 defenses. GM Buddy Nix stated that Buffalo would continue to draft 3-4 personnel. How would this work?
After the pre-season and a first game, an answer is beginning to formulate. Buffalo isn't playing standard 3-4 or 4-3 fronts. Buffalo's defense looks like Baltimore's defense, which shifts between 3-4 and 4-3 variants without changing personnel. Edwards used to coach for Marvin Lewis, formerly the defensive coordinator for the then-Super Bowl champion Ravens, so the connection between the two defenses should come as no surprise. Add in Wannstedt's expertise, and Buffalo has the schematic brainpower to present offenses with some challenges.
For this story, we're using a standard set of starting Bills defenders. Linebackers are squares and linemen are inverted triangles. The starting nose tackle is Kyle Williams, flanked at end by Marcell Dareus and Dwan Edwards. The linebackers are Shawne Merriman, Chris Kelsay, Nick Barnett and Kirk Morrison. These players are pretty close to the starters, but were selected to show some of the schematic advantages and how these players are being positioned for success.
Bullough-Fairbanks 30 Front Defense
This is the standard 3-4 defense from the 1980s, used most successfully by Bill Parcells and his coaching tree. Buffalo can play this defense, and does at times, but this set presents some challenges to Buffalo's personnel. Notably, Williams isn't an ideal two-gap nose tackle, and having Barnett take on the left guard all game isn't a great idea. This defense is essentially a "variant" used to keep offenses off balance, despite being a base defensive scheme.
30 Under Front
The "under" in the name describes the defensive line in respect to the strong side of the offensive formation. In and "under" front, the line shifts away from the offensive strong side. For context, the strong side is the tight end side. Here we see Edwards' role essentially unchanged as a five-technique end. Williams shifts to a one-technique nose tackle, ready to burst into the weak side A-gap. Dareus moves away from the offensive tackle into a three-technique, commanding the attention of both the guard and tackle. Kelsay puts his hand on the ground and becomes an end. Morrison remains on the strong side to take on blocks. The advantages here are the positioning of Merriman and Barnett. Merriman is playing in space and free to pursue, while Barnett is covered by Williams and Edwards and free to roam.
30 Over Front
The defensive line has shifted to the strong side in the "over." Edwards and Dareus switch sides, allowing Dareus to play three-technique and Edwards to play five-technique. Kelsay remains in position, but is upright with linebacker responsibilities. Merriman puts his hand on the ground and threatens the left tackle. Morrison and Barnett's roles are unchanged, though the left guard does have some increased ability to get to Barnett in the over front, depending on Dareus' positioning.
At first glance, there seems to be little difference between the 30 Over and this 46 variant - but the little things count. Here, both ends are playing inside of the offensive tackles and over the offensive B gaps. This keeps the inside linebackers free. Kelsay and Merriman play similar to the 30 Under front. Part of the key is the linebackers. Morrison is less of a 30 Front "Mike" inside linebacker, and more of a true Mike linebacker in a 4-3, while Barnett is playing more like a weakside linebacker, since he's covered by Williams, Dareus, and Kelsay. Morrison and Barnett have the ability to shift more to the strong side and create even more of a 4-3 look, as well.
Again, this looks very similar to the previous 46 and 30 fronts. The difference here is that Merriman is now playing end with Kelsay at outside linebacker. Edwards and Dareus can flip sides. Most importantly, Morrison and Barnett switched sides. Morrison is again a traditional middle linebacker. The benefit here is the freedom allowed for Barnett. He may have a gap responsibility, but with the guard and tackle occupied, he has the ability to flow to the ball unhindered.
Carrington at Outside Linebacker
Here, Buffalo is playing a similar defense to many of the samples above. Alex Carrington is manning an "outside linebacker" position. In reality, Carrington is playing a wide defensive end that can be seen in most 40 front defenses. His size helps control the tight end, which Buffalo had issues with in 2010. His length also helps the defense control the edge, another 2010 problem spot. As Buffalo acquires more outside edge rusher types, Carrington may move back into a more traditional end position.
This has been, at best, an overview. There are many more variations of these defenses based on small adjustments in player positioning, as well as player responsibilities. If any of us were privy to Edwards' playbook, it would likely be confusing during a first read. That's the point. Buffalo spent four years lining up in the same spot and doing the same thing while playing a Tampa 2. That works if most of the front seven visits Honolulu each year. For most teams, it doesn't.
Nix is justified in saying that the team will continue to draft for a 3-4 set. Any player that Buffalo drafts that can play in a 3-4 can play in this defense. Not all 4-3 players can. A college 4-3 end that cannot stand up and play outside linebacker doesn't work in this scheme. A shorter, one-gap college defensive tackle probably can't play in this defense. Many smaller college weakside linebackers can't play in this scheme.
Gailey and Edwards, along with Wannstedt, have decided to play a multiple defense. Call it necessity or common sense. As the defense breaks their huddle, the quarterback has to carefully check the defense's alignment and positioning. Pre-snap reads become more difficult, since the defense can do many things from some similar sets. Is this defense going to confuse Tom Brady to an extent that he plays poorly? Not likely. It could confuse a lineman or receiver, for example, for a half-second, and that might be what it takes to get pressure into the quarterback's face. Or stop a run. At a minimum, this defense is a sure upgrade schematically. As Nix continues to add players, this defensive scheme has a chance to be very good.