Throughout May and heading into training camp, the NFP’s Matt Bowen will take you inside the playbooks of the NFL -- basic defenses, the running game, red-zone passing, fire zones, etc. -- to give you a better understanding of what your favorite teams are doing on Sundays.

Last week, we discussed the Tampa 2 coverage and broke down the scheme on the chalkboard. A 2-deep, 5-under defense that turns into a 3-deep, 4-under scheme once the middle linebacker runs the middle of the field with any inside vertical scheme. A basic defense, but just like installation in the NFL offseason, we will work our way through the core coverages.

Today, let’s look at the classic version of the 3-deep, 4-under defense that is played at all levels of football, but still has a home in the NFL: Cover 3. Three defenders split the top of the defense into deep thirds, while the four underneath players take care of the flat, the curl and the middle hook.

Why is a defense that is still taught at the high school level so prevalent on Sundays? Simple: the ability to create an eight-man front. We talk about that extra player in the box all of the time, and in Cover 3, that is the strong safety dropping down to the closed side (TE side) for run support. A defense that is part of every playbook and a lead call for Tampa 2 teams who want that extra defender in the front in running situations.

Let’s check out the chalkboard with the defense in a base 4-3 alignment vs. pro personnel (2WR, 2RB, 1TE) on offense with split backs…

I put the defense in a 2-shell, giving the secondary the look of two safeties ready to roll to the deep half. The corners are aligned at a man-to-man depth (around 7 yards) where they can walk up to the line to jam in Cover 2, play Cover 4 responsibilities or drop to the deep third. At the snap, the strong safety drops down into the box and the free safety rolls to the deep middle of the field.

Think of Bob Sanders — when healthy — of Indianapolis. In my opinion, the best in-the-box safety in the game because he has the ability to contain any run that presses the edge of the defense, fill any cutback lanes on weak-side runs and make plays in the passing game when he is part of the defensive front.

Let’s break down the defense by position…

DE- Align as a “5” technique — Outside eye up the OT. Attack "C" to "B" gap on run.
N- Align as a “1” technique — outside eye of the OC. Attack “A” gap on run.
DT- Align as a “3” technique — inside eye of the OG. Attack “B” gap on run.
DE- Align as a “7” technique — head up the TE. Attack “C” gap on run.
WB- Align head up the OT. Contain vs. run, drop to curl/flat vs. pass.
MB- Align strong side “A” gap. Drop to weak hook/curl vs. pass. Fill "A" gap strong.
SB- Align outside eye of OT. Drop to strong hook/curl vs. pass. Fill inside fullback lead block vs. run strong, scrape to "A" gap vs. run away.
C- Drop to deep outside 1/3 with outside leverage on No. 1, zone technique (back to sideline)
FS- Drop to deep middle 1/3 with enough depth to get over the top of any outside vertical by No. 1.
SS- Drop into box at snap with 5x3 alignment on TE. Contain vs. run, drop to curl/flat vs. pass.
C- Drop to deep outside 1/3 with outside leverage on No. 1, zone technique (back to sideline)

Some keys to think about…

The Will Linebacker and the SS play important roles in both the run and pass game. Versus any outside run weak to the Will or strong to the SS (think of the outside zone, Power O, Lead Open, Lead Strong) they must contain and force the run back to their defensive help. This requires them to “hammer” the lead block (lead with inside shoulder) and close the gap between blocker and ball carrier.

In the pass game, both players have to work through the curl but cannot get outflanked by any receiver to the flat. Think of the Curl/Flat combo by the offense. The Will and the SS cannot get beat to the outside by any flat route. That is why QBs will hold the ball until the defender breaks to the flat to throw the curl route.

The corners must maintain outside leverage and use the free safety to their advantage. If they get beat to their outside, they have no help to rely on. That is why they use zone technique (back to the sideline) and widen with any vertical release to protect the sideline.

The free safety is the top of the defense. He must honor his responsibilities and not chase any intermediate routes. Offenses will run a deep dig (15-yard square in) to entice the free safety to jump the route — while running a post from the opposite side of the field, leaving the corner naked and playing from outside in with zero help. A classic Cover 3-beater.

This is an eight-man front. If a defense can’t contain the running game with this defense, it will be a long, long Sunday.

Up Next: Base Open Side Fire Zone

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