It still blows my mind how this team doesn't run a 3-4 defense

[805BoysInBlue]

So cause we have a couple of DEs that can play OLB were supposed to change the entire front 7? We dont have the DEs and NT to play a 3-4.

 

[xwalker]

WRT Osa being a good 3-4 DE, the DEs you want in the classic 3-4 are not just big, they're also very tall or long. Think of Spears. You want your 3-4 DE to line head-up on the tackles and keep the tackle out of their chest, so they can defend 2 gaps. You don't want a DE who gets engulfed.

Osa is short, but he's got really long arms, so I wouldn't categorically write him off. But he gets engulfed right now as a one-gap player, and you'd be putting him in more of those bad situations as a two-gap player. He could probably make it work, cause good football players are good football players, but it's not his best fit.

The holy grail of the old school 3-4 was the "pressure five" - the DE who could cover two gaps in run defense and also get to the the QB on passing plays. Those dudes were unicorns. They were never big sack guys, because they had to run straight through a tackle on their pass rush, but they could give the defense pressure without blitzing and they freed up the rush LBs even further. Most of your good 3-4 defenses had one - off my head, I'm thinking of players like Justin Smith with the Niners, Aaron Smith with the Steelers, Richard Seymour, or Haloti Ngata.

Aaron Donald played 3-4 ...

 

[beware_d-ware]

Aaron Donald played 3-4 ...

Wade Phillips and Brandon Staley used Donald in a one gap 3-4 scheme. Heck, Phillips pretty much invented the one gap 3-4.

One gap 3-4 looks very much like a 4-3 under front, especially if you're taking one LB off the field in nickel . In both a 4-2 one gap nickel, and a 3-3 one gap nickel, you have three linemen gap shooting, two true off-ball LBs, and one pass rusher out wide speed rushing. Whether you want to call that last guy an LB or a DE, his role is the same.

That's why I think the 3-4 vs 4-3 distinction isn't really relevant in the NFL today. It's become a difference of small details, like whether you want to have your strong side DE shoot the gap on the tackle's inside shoulder or on his outside shoulder. The differences in personnel aren't as stark as "Monte Kiffin with Warren Sapp and Derrick Brooks" vs "Dick LeBeau with Casey Hampton and Joey Porter" any more.