Hub Arkush at chicagofootball.com makes me feel a bit better about the Bears transition to a 3-4 defense as he talks about the variations in the scheme:
“The original 3-4 defenses were very different from the 4-3 and even many of today’s 3-4s in that they were two-gap schemes while the 4-3 and many of today’s 3-4s are one-gap defenses.”
“In a traditional 3-4 defense, the nose tackle is responsible for both A-gaps, and the defensive ends, also known as five-techniques, are required to fill the gap between the guard and tackle on their side and to set the edge so that no running backs can get outside the tackles.
“When one of the three defensive linemen gets to the quarterback, that’s a bonus, as the principle pass rushers in the 3-4 are the linebackers, who will rush in various blitz combinations.”
“[Bears general manager Ryan Pace said] ‘[W]e’ll be base 3-4, that’s accurate and that’s what [defensive coordinator Vic Fangio is] comfortable with, but the best coaches, they find ways to maximize their players’ skill sets. I know Vic’s going to do that.'”
“What makes that possible is the evolution of the one-gap 3-4 schemes in which gap responsibility is spread between the three linemen up front and the linebackers.
“As an example, in this scheme the nose tackle will fill one of the A-gaps and the strong-side inside linebacker will be responsible for the other gap, which he will either shoot if the play comes through it, or flow in the direction of the play if it doesn’t.
“The key to this scheme is each player in the front seven must make a series of reads as the play develops. Gap integrity is a must.
“This scheme is primarily what Fangio used in San Francisco because he really didn’t have the traditional two-gap space-eaters there, either.
“Teams in the NFL today that play a 3-4 base scheme rarely stick strictly with one style or the other.”
Like many Bears fans, I’ve been able to find a fair bit of information about the traditional, two gap 3-4 defense. Finding information about the one gap form of the defense has been harder to come by. In that respect, this was a valuable article.
Until now, I’ve assumed the Bears would likely play one form of this defense or the other. But Arkush makes it clear that’s not necessarily the case. It seems that the Bears will slide in and out of the two different forms depending upon the personnel on the field. If Jay Ratliff is in as a nose tackle, he’ll likely be responsible for only one A gap while the strong side inside linebacker will take the other. If, on the other hand, it’s Ego Ferguson, they may have him two gap it. Indeed, its conceivable that the defensive linemen and linebackers up and down the line won’t all be playing the same style at once.
What this all means is that the Bears will be able to more easily adjust to the change in scheme than many would have you believe. The skills required to play the one gap style of the 3-4 are similar up and down the line to those required to play the style of 4-3 the Bears played last year. There are still problems but the Bears should be able to work around them. Add that to the fact that they’ll likely be in hybrid four man fronts in sub packages and the Bears won’t have too tough of a time adapting to whatever style Fangio decides to play.