Tennessee spent much of this game using the pyramid defense against the flexbone offense. This is a classic 4-3 with the OLBs right behind the defensive ends and the MLB sitting way back. This is a pretty classic formation for defending the flexbone. If the defensive end is the read on the dive (e.g. if the DE cuts inside the QB keeps it) and the OLB is the read on the pitch (if the OLB takes the QB, then he pitches it). Leaving the MLB far back gives him a better read on the direction of the play, and makes it harder for the offensive line to block him because they have to go farther.
The wrinkle that they added was that they played their defensive tackles about a mile off of the ball while leaving their ends a little closer to the line, but in a standing position rather than the three point stance. Doing this, the ends should have some extra lateral mobility which would hypothetically make it harder for Taquon Marshall to read whether he was crashing towards the B-back dive or shuffling outside to take the quarterback on the veer.
By leaving their tackles so far off the offensive line, it makes it easier for them to impede the interior offensive linemen who are trying to get to the second level. On some of the earliest plays of the game they took this even farther. Watch below as the Tennessee defensive tackles essentially cut block some Tech offensive linemen. In this play you can also see the effect of having the defensive ends standing up. Focus on Jahaziel Lee, the playside tackle. His job on this play is to get the middle linebacker, but the defensive end is in a better position when he’s standing up to slow down Lee just enough that Lee is unable to get the middle linebacker. This play was stopped for little gain.
The natural attack on this defense is to run the dive and take the extra yards that the linemen are giving you. Tech stuck with the perimeter early, but started to have more success when they committed to hitting the interior in the middle portion of the game.
Jacksonville State started the game using the other main formation. They only played three down linemen while placing the outside linebackers very close the line and the two inside linebackers each “taking a side”.
The Gamecocks also tried to defend the option using the oldest strategy in the book, 8 men in the box. It seems like an obvious defense to a run heavy offense such as Georgia Tech, but it does have it’s weaknesses. If a rocket toss or other quick hit to the outside gets around the linebackers, then their is only one defender to beat for a very long gain. The other, of course, is passing. That is why it is so important to have a quarterback who is at least a threat to pass the ball. Once the Yellow Jackets started to throw the ball, they had more success on offense. I don’t expect other teams to regularly play 8 men in the box like JSU did.
The final thing that Jacksonville State did was try to shift the defensive line right before the snap to try to confuse the offensive linemen on blocking assignments (example below). This tactic has been successful in the past, just look at Clemson in 2015 (or don’t cause that wasn’t fun). But, this can be mitigated by a disciplined offensive line and can even backfire if they cut it too close to the snap and get blown off the ball. We will definitely see this later this year.