What is the 3-3 stack? Different versions of the 3-3 stack and Broken Stack 3 safety system
The 3-3 stack and broken stack 3 safety systems
People are falling in love with the 3-3 stack and 3-3, 3 safety broken stack system. It is a good defense but not everyone plays it the same way. Some great coaches run both defenses. I'll just compare the 2 I have been looking at, although there are many great ones. Miss State, Iowa State, TCU and Cincinatti play the 3 safety defense. Tony Gibson is more a 3-3 stack with 4-2-5 principles, especially on the back end.
The advantages of going to a 3 hand down system are that it allows more speed on the field to play the spread teams we seem to face on a weekly basis. Most teams are based out of 11 and more and more are running 10 personnel. Both the 3 safety and 3-3 stack teams can get more speed on the field at the Linebacker and SS position. The 3 safety system allows you flexibility in run fits as you can show different looks and change the run support with more flexibility.
There are similarities and differences between the 2. I took a look at Tony Gibson a true 3-3 stack team and compared him to Iowa State a 3-3 broken stack system.
Here's what I found:
Similarities:
1. They are both 3 hands fronts in which you will get either a nose and 2, 5 techniques or 2, 4i at De. You will aso see a compbination of the 2.
2. They will often times play with 3 LB and 5 dbs.
3. They will play a variety of coverages including 3 safeties. Some cover 3, cover 1 and cover 2 will be analyzed further.
Differences
1. The true 3-3 stack run by Gibson will not break the stack as often as the broken stack teams. He will often use the safety in run support filling very hard off the rb.
2. The 3-3 stack run by Gibson will make adjustments to a 3 safety with the sam linebacker. The broken stack system will do a ton with the weak side lb/safety. He will often drop into coverage and be the 3rd safety. This is a major difference.
3. Run fits-The Gibson system will often pinch and have the mike play the c gap. The safety will fill off the running back in the Gibson system and you will often see him make plays in the backfield. In the 3 safety, the free safety will often fill on the backside away from the rb.
3 In the 3 safety Iowas State look 3rd inside linebacker will often adjust and be out on #2. In Gibson's defense this will be the sam and they will keep the LB inside box. They will not be as likely to break the box. If there is an h back, Gibson will have one of the LB align over him.(see below) It has more 4-2 principles on the back end.
4. They will often adjust with the sam linebacker in the Gibson model and stay stacked with the other 2 LB. Notice just the one lb moves to the side of the h back. They keep the integrity of the front with the other 2 LB's staying stacked.
RUN FITS
Gibson Stack:
Let's look at a few examples of how well they fit the run on all three levels. UNC comes out in 11 personnel and they align in their odd front cover 3. They move the De inside and watch the spill overlap technique. DE spill everything, LB box it to the safety. Mike often will play the c gap with all the pinching up front. Safety just fills off the rb. Just mirrors him and is often a free hitter.
Pre snap plus 1 in the run game
nice job with the DE coming hard inside forcing the ball bounced outside.
nice job with the spill as it is forced out side. Safety plays off the RB.
safety unblocked!
The Safety usually just plays off the rb in the scheme.
2nd example of how they play it on all three levels.
They will often move with the de, he's hard inside so they get the spill, with the overlap LB. Safety usually fills off the back unless they change that with a call.
Mike is a C Gap player, Nose usually off A, OLB will play the cutback.
Again you can see the overlap and safety filing as ball gets bounced.
safety there to make the tackle!
One more example as you can see the de on the left spill it and both LB filling over the top to the b and c gap.
ILB overlap to b and c gap. Sam forces it back inside.
LB is there and the safety if run will be there to fill.
Great design, Only problem is it's play action so you see the safety put on the brakes
Here's 2 more clips of how explosive the safeties are in the run fits. They come down hill in a hurry when they read run.
Another example is vs Miss State in 2021. They run cover 3 and then cover 2 hole. In the first example the sam is a flat defender. When they go cover 3 they have the sam as the flat at times . Then on the next clip they go cover 2 hole and the sam is a deep half player. Again all of their coverage variations are often dictated by the sam and his movements and alignment. In the broken stack, the free or will is the adjuster.
See the zone coverage developing .
Mike carries 3 vertically.
On the next play they go cover 2 hole. The sam is 2nd from the bottom of the screen. He becomes the deep 1/2 player
You see the sam starting to become the deep 1/2 player.
You can see the cover 2 hole coverage with a shallow lb playing the shallow crossing area and the middle safety playing the deep hole.
Here are 2 clips of NC State using the sam in different roles in coverage.
So, that covers the Gibson model, you can see how they use the sam as both a lb underneath, a deep 1/3 or even a a deep 1/2 player but also as an underneath cover man in their man principles.
Broken Stack System
Here you will see the run fits by the safety usually to the same side of the rb or away from the strength. The FS is more of a cutback player. You can see it on the 3 images below how he fits away from the strength and plays cutback first.
See the FS
plays cutback.
Iowa State run game fills
Iowa State
Fronts
At Iowa State 3-3 stack will only be played vs 2x2 10 personnel. It seems like they break it but will start 3 safety. They have 3 LB and the 3rd LB is often out on #2. It makes their box very light. This is a major difference as you can see their lb split the difference between the tackle and #2.
Basically, any other set they will break the stack look. Here it's a 3-1 front with the safety at 10 yards.
va 20
Strong LB always goes to the formation and is over #2. Again a 5 man box.
vs 12. Front is a 3-4 with the weak safety acting like the weak side OLB
Vs 11 personnel with a tight end. 3-4 with the overhand with the weak fs/hybrid player playing to the boundary. Starting with the 3 safety look. You can see the 3rd lb out on 2.
again formation to the boundary and the stack is broken with the 3 safety look. Again more zone.
11 formation to the boundary. They keep the cover 2 look to the field but they still set the front to the boundary. Again broken into a 3-2 defense.
Broken again with the sam over the 3x1 side but off splitting 2 and 3.
vs 20 its a 3-2 box inside with 2 olb
va Oklahoma 21
Vs 3x 1 10 personnel and 3-1 it's a 3-2 broken look with the front side lb splitting 2 and 3 and both safeties moving over. The weak safety lb becomes a deep half player.
Vs 10 personnel, you will get a true 3-1 look with 3 safeties. Again the weak safety is on the hash to the bottom of the screen on the 20 yard line.
Iowa State Cover 3
Here's a basic cover 3 from Iowa State vs TCU. They roll to 3 with 5 underneath defenders and a 3 deep secondary look. 2 clips below
Weak safety comes down to play the flat, Field safety comes down to play the flat and it turns into a cover 3.
Again they go cover 3 with the coverage.
See the rotation as the free safety drops and they are in cover 3
1/4 1/4 half coverage concept with a spy vs Texas
1/4 to the field and 1/2 field to the boundary.
I hope you enjoyed this article. From what Ive seen Gibson will play a true 3-3 stack and because of the man to man concepts can stay in it. The broken stack system is a little more zone based and teams seem to get out of it more with the 3 safety look.