Without moving the front on a line stunt, a defensive coordinator can set up the fits to create gap exchanges and stay sound against zone read teams. Even if a team is running a simple inside zone scheme, teaching gap exchanges between the front seven can allow the front to “cut-off” the runningback’s path and force a cutback to free hitting linebacker. Understanding the structure of a front is key for any defense to be successful. Teaching the LBs to read their “anchor points” can allow the defense to be fluid against zone schemes. Defensive lineman must know their gap assignments just as well as the LBs. In the age of spread, it is important for the front seven to understand how each gap is going to be fit and how each player’s movements effects the link behind them (DL-LB-Secondary). All great defenses start with a solid technical structure.
Spread offenses want to attack the open “B” gap and the conflicted LB. The zone read is nothing more than a modified Dive Option. Add a bubble route (or any receiver screen) and the offense is running a modern version of the Triple Option (the offense can use orbit motion to create the same look too). 
Even if the offense is aligned in a spread set, option structure is still there. As a DC starts to game plan and create a defense to defend a spread attack, he must look at a zone-read heavy offense as though he was attacking a Triple Option attack. Someone has to take the dive, the QB, and the pitch. How a DC chooses to set the front will determine who carries the ball versus a zone read/option team. In the diagram to the left, the defense is set up in an Over Front to a 10 personnel 2×2 set. The Sam can cover down to the slot because he does not have a box fit. The Mike and Will each have a gap to hold versus a run. Since the front is set to the RB (5 and 3 technique), the most likely scenario versus a zone read is a handoff (dive), the Will folds into his box position and the Sam takes the bubble (pitch) away from the play. By setting the front to the back, the DC has created a predictable situation in which the QB will hand the ball off to the RB. Just on alignment alone, a DC can force the offense’s hand. Defending zone-read heavy teams is all about cover downs and changing the “B” gap. The most important decision a DC can make versus spread teams that run read/option plays is to decide who is the worst ball carrier, and force that player to carry the load.
Creating Natural Gap Exchanges
The Over Front
The best way to defend against the modern spread is actually one of the oldest fronts in football, the Over Front. This particular front, when used against the spread, allows the defense to stay even, cover down, and create problems for teams wanting to run simple RPOs. The Over Front’s structure lends itself to defending the spread. One of the main objectives for any defense is creating a lack of space. The Over Front forces the offense into the boundary. By covering down the Sam, the defense has essentially eliminated the pitch and created a plus-one in the pass distribution. The 5 and 3 tech’s to the field create a natural wall against the run. The Mike fills the strong-side “A” and the Will is the “fold player” to the boundary. The Will is the conflict player, but because he is away from the QB’s read, he is allowed to fold into the box with aggression (the offense can flip the read and take advantage of an aggressive Will though). Here is a diagram of the front side of an Over Front versus a typical zone read:
In the diagram above, the DE to the field keeps his shoulder’s square and works off the OT’s hip. His eyes are on the QB and will attack him if he decides to pull. The square shoulders give the QB a “give” read. The 3 tech. and the Mike attack their gaps and the RB. If the 3 tech. were to cross the face of the Mike, the Mike will scrape to the next open gap, most likely the “B.” This natural gap exchange allows the D-lineman to be aggressive to the ball versus zone blocking, literally cutting off the RB. The LBs react to any D-lineman crossing their face and “exchange” their gaps. To the boundary, the Will folds into any open gap. In this case, most likely the weak side “B.”
“Field Call” Versus FIB
By setting the front to the field, the DC has decided to protect the open space and force the offense to play to the boundary. Since the front is set to the field, the read has changed for the offense. The DE, knowing he has the Nose, is the dive player. There is an open “B” gap and the nearest “anchor point” is in the “A” (Nose). This open gap gives the DE the freedom to chase the RB versus zone read. In the diagram above, the QB pulls the ball because the DE crashes down hard on the dive read. The Will has the luxury of sitting still because he knows when the RB is to him the DE will take the dive and his key is now the QB (and drives on the screen when the ball is thrown). The DS takes the “pitch” or bubble/WR screen. Even though the Mike has the strong side “A” gap, the Nose works to cut off the RB and essentially closes the opposite “A.” This allows the Mike to “belly key” back to the weak side. If the QB gives the ball, the Mike will attack his gap, if the QB pulls, he will scrap to the outside and be the plus-one. These simple gap exchanges play on the way spread teams zone block. The DL cuts off the backside of the OL with zone away making the OL chase and not allowing them to climb, even getting them out of position when trying to block the LBs.
Changing It Up
Offenses can take advantage of these gap exchanges. A way to create single-gap fits is to give the DE’s “hold” calls or use post-snap line movement to change the read for the QB and change the “B” gap. When offenses figure out the way you are fitting their zone schemes they can “pin” the LBs using a simple man scheme and get the LBs out of position. It is important to always teach LBs flow reads. Even though their eyes are on their guards and anchor points, they need to understand the path of the back and the OL’s block path (to aid against stretch).
Hold Call
As stated above, one of the simplest ways to change the read for the QB and create a situation where every player holds their gap is to give a “hold” call to the DEs. This makes them hold their outside alignment, and essentially “box” everything. The read for the QB versus a “hold” call should be a give. This allows the Mike and Will to fit their gaps without worrying about a gap exchange. Be aware that if the offense is reading the Will for an RPO, the folding Will is giving the QB a throw read and the DS is left one-on-one versus a slot (with late support from the Will). The diagram below shows a “hold” call versus 10 pers. 2×2 [FIB]:
Interior Line Movement
One of the safest and most effective ways to challenge a zone heavy offense is to use post-snap interior line movement to change the “B” gaps and the reads for the QB. Knowing that spread offenses attack the open “B” gap, the best way to attack them would be to change where that gap is located. OC’s call certain plays knowing how the defense will line up. For instance, versus an Over Front with the RB set to the field in a 10 per. 2×2 scheme, the QB knows the DE will hold his alignment and will most likely give the RB the ball in a zone read. Changing the “B” gap with line movement changes the read and can make the QB hesitate or give the ball to the RB only to be tackled for no gain. Hesitation in an read/option attack is deadly.
In the diagram above, the defense is running a post-snap interior line movement. This changes the read from a give read to a pull read. The DE, knowing that the 3 tech. is leaving, has switched his responsibility from QB to dive and can now crash down on the RB. The Mike, knowing the “A” and “B” gaps will be taken by the movement, can rock to the field with zone away (his responsibility is now the QB). The pass distribution to the two WRs hasn’t changed, and the Will to the boundary can fold into the formation. This is what the same movement would look like to an FIB set:
The read for the QB changes to a give and the RB runs right into stunting lineman. The goal here is for the 3 tech. to cut off the Center’s backside and go unblocked. The Nose crosses the guard’s face and sets a wall to the field. The Mike rocks back and takes the cutback of the RB. The Will holds his position and folds into the formation when the ball is handed off in case the RB hits it frontside. The Will can hold his position with zone to him because the Nose and 3 tech. should make the RB cut back. The point behind line movement is to create a sudden cutback, stop the momentum of the RB, and force him into an unblocked LB.
Conclusion
The structure of the defense should allow it the flexibility to line up to multiple sets and have an answer to multiple plays. Teaching gap exchange allows the defense to get post-snap movement without actually calling a stunt (hold gap with zone to, cut off with zone away). When needed, a DC can call a line stunt to change the gaps and reads. Making reads hard on a QB is essential versus any read/option based offense. The use of interior line movement can be a great asset when it comes to making the QB work for those RPO reads. A defense has to change things up and can’t stay static. Creating a flexible and fluid structure is essential for a modern defense to be adaptive and responsive to what modern spread offenses are showing them. How a DC sets up the offense will directly effect the plays it sees. Using an Over Front to protect the field and ensuring cover downs forces the offense to be left-handed and play in limited space.
If you’d like to read my previous article on Attacking the Zone Read click HERE.
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