Continuing with our series of defensive coverage shells, this week we’ll take a closer look at the three-deep zone defense, which is more commonly known as the cover 3.
Green Bay Packers defensive coordinator Dom Capers predominantly prefers the single-high safety look, but he has deployed the cover 2 shell frequently over the years.
However, the Packers don’t use the cover 3 all that often, but it’s a defense that every NFL team must have in their arsenal because what it brings to the table.
Of course, this article comes with my standard disclaimer that this is an oversimplification for illustrative purposes only.
Cover 3 Defense Defined
When defending the field, the defense usually divides the area vertically into â€œhalves.â€ The underneath half typically extends 7 yards from the line of scrimmage and the deep half usually extends 15-20 from the line of scrimmage.
In the three-deep zoneÂ defense (cover 3), the free safety and both cornerbacks play zone defense and each guard a thirdÂ of the deep half. They must cover any receiver entering their respectiveÂ thirdÂ of the field and drive towards to the ball once it is in the air. Additionally, they must carry the receivers vertically all the way to the goal line.
The GIF below highlights the assignments.
Strengths of Cover 3
There is no perfect defense in football. If the defense sells out to stop the run, they are extremely vulnerable to the pass. Likewise, setting up a strong back end to guard the pass makes them susceptible to the pass.
The cover 3 is a compromise defense of sorts. Because the deep third is covered by the free safety and both cornerbacks, the strong safety is free to align in the box.
This means the defense can play eight in the box to stop the run. The front seven (defensive line and linebackers) are in the box in addition to the strong safety.
In a nutshell, the cover 3 allows the defense the flexibility. It can be considered a “jack of all trades” defense. It is a very popular run defense, with pass flex, in the NFL because it allows the defense to pack eight in the box and still drop seven into zone pass coverage.