Teams using the 4-3 defensive system will benefit the most by becoming adept at mastering both the Over and the Under front line spacing alignments.
The term Over is used to describe any defensive front where the strong side defensive tackle will take a '3' technique position opposite the strong side offensive guard. The back side defensive tackle will move over toward the strong side and position himself in a '1' technique.
The term Under is used to describe any defensive front where the strong side defensive tackle is aligned in a '1' technique over the strong side guard, while the back side defensive tackle takes a '3' technique position across from the opposite offensive guard.
- When there is a tight end, whether an over or an under call, the strong side outside linebacker (Sam) will move to the line of scrimmage to the tight end's outside shoulder.
- The positioning of the back side outside linebacker (Will) and the middle linebacker (Mike) will vary with the over or under call, whether or not a specific blitz is called, and what formation the offense is using.
- When aligned in the Under front, be aware of the potential problem the offense can create if it can be successful at running into the back side A-gap.
- The Over/Under front can be attacked by a midline option team, as the quarterback will determine the side of the midline call according to the spacing of the defense tackles.
- Take advantage of the multiple blitzing and pass coverage schemes provided by the Over/Under fronts.