Chalk Talk: Cover Three

Generally, amongst casual football fans (there's nothing wrong with that) the thought of zone coverage means that a player is dropping to a zone and defending that land. As long as they secure that small part of the field, they're good, and don't need to worry about anything else.

That, however, is not the case. As evidenced by the cover 3.

I'll talk about it from a 4-3 perspective, then I'll tell you how it equates with the 3-4 with and without the blitz (simply, though. Not going to go into too much detail there.)

The cover 3 generally has a single high safety covering the deep middle of the field. He's responsible from hash to hash (dependent on where the ball is, but we'll assume the ball is in the middle of the field for this)

Generally, you'll see two corners drop. One corner will be responsible from one sideline to the hash. The other will be responsible from the other sideline to the hash. So each is responsible for 1/3 of the deep field.

The corners are reading #2 to their side. The numbering system is from outside in to the center on each side. So the furthest receiver from the center is #1, the next is #2, then #3, then #4. So, for instance...

So the offense lines up in a typical pro set. Split end to one side, flanker/tight end to the other.

To the flanker/TE side, the flanker is lined up furtest outside, he's #1.

The TE is next, he'll be #2.

The back that swings in that direction becomes #3.

To the other side, the Split End is #1 and the back that swings that way is #2.

So again, the corners are keying #2. Which in this example would have the strong side corner keying the tight end and the weak corner keying the back to his side.

So while the strong corner is watching the tight end, if that tight end goes up the seam, he'll have to keep an eye on him, as he's headed towards his responsibility of deep thirds. If he sees the tight end break towards the flats, he's going to shift his attention to #1, to see what route combinations may be occuring. If nothing shows to his zone (deep third) he can scan the rest of the field for any crossing routes. If that's clear, he can help the flat defender with the route combination underneath. If there is any threat to his zone, he must play his zone.

The weak corner does the same, except keying the running back then combination routes with the split end.

A safety will be rolled up to linebacker alignment, most likely the strong safety. He'll cover the curl/flat zone to his side of the field. He's keying #2 then looking to #3. If the TE runs deep, the SS will pass him off to the corner (as discussed above) and he'll turn his attention to the back out of the backfield (who is #3). If the TE does not go vertical, he stays in his curl/flat responsibility.

Now, let's go back to the FS, who has hash to hash responsibility and is the third part of the deep thirds trifecta. His first read is the uncovered offensive linemen. Uncovered means that there is no defensive player lined up head up or to the OL's inside gap. If the OL pass sets, he will get into a zone drop almost straight back. If the OL run blocks, his responsibility is to fill blood alley (my favorite football term. It means he's coming down hill hard and trying to knock someone out).

His key versus pass is #2 to both sides. If #2 doesn't show, he'll can the field for any threats coming to his third of the field. #1 to both sides would be the next logical choice of going deep into that zone.

Now let's talk about the SAM backer. The SAM is the strong side backer and he'll key the TE. He'll take the hook zone, which to give a general description is the area that is in front of the offensive tackle or around there and about 5-10 yards downfield. He's looking up the strong #2 first (TE in this case) and then the strong #3 (RB). He wants to attack any short dump offs in the hook zone from the inside out. Meaning he wants to force the receiver to get pushed to the sideline.

The WILL (weak side backer) has the same job as the strong safety, essentially.

The MIKE will play the hole and help with any routes to the hook zones.

So how does this translate into the 3-4? Well, with no blitz called, it gives you an extra coverage guy. The secondary remains the same.

The SS will take the flats still to the strong side. The SAM will take the curl zone, which is a bit different. Before, the SS had curl/flats. Now the SS would be more concerned with the flats while still paying attention to the curl. The MIKE will align to the strong side of the formation and he'll take the hook zone. The JACK will align to the weak side of the formation and he'll play hook to curl zone. The WILL keeps the same responsibility to his side, playing curl to flats.

With a blitz on from the 3-4 look, it operates the same way as the 4-3 version, except changing jobs. If the WILL blitzes off the edge, the JACK will take the curl/flats, MIKE plays the hole, SAM takes hook, SS takes curl/flats and the secondary remains the same.

If the QB runs a sprint pass (a pass where he's on the run) all the zones shift TO the sprint side. So the backside flats defender might not play as far to the sideline as he generally would. That's a tough throw for any quarterback to make across his body, so he'll probably get more depth and adjust his zone with every step the quarterback makes in the opposite direction.

I want to point out the cover 3's weaknesses. First and foremost, the cover 3 can be picked apart via flat routes (Short routes near the sideline) or routes that are just a bit deeper than the flats, such as a curl. Why? Because the linebacker/SS are reading multiple receivers, and because the corners are dropping from that zone, it's vacated for a moment. Another weakness is the area between the three deep defenders (the area of each of the hashes).

If you have any questions, feel free to ask

A shame that a worthy thread like this, from a great contributor, gets pushed to the bottom of the first page when there's nothing going on in the offseason.

A well-deserved bump!

Here is a diagram of what it looks like

Here is a diagram of the soft zones in a Cover 3

A shame that a worthy thread like this, from a great contributor, gets pushed to the bottom of the first page when there's nothing going on in the offseason.

A well-deserved bump!

Agreed,(though to be fair,you have to give people a chance to "google."

The Chalk Talk threads are one of the few things worth reading in the Stadium most of the time! Thanks for that KDawg!

Having played football during HS, I know a little about the game. I actually enjoy explaining things like this to friends and other fans.

Thanks KDawg. It's nice to actually have a post about football.

First and foremost, the cover 3 can be picked apart via flat routes (Short routes near the sideline) or routes that are just a bit deeper than the flats, such as a curl. Why? Because the linebacker/SS are reading multiple receivers, and because the corners are dropping from that zone, it's vacated for a moment.

KDawg, how do you feel the new rules changes will effect the Cover 3?

Defenseless players are now defined as: "those throwing a pass; attempting or completing a catch without having time to ward off or avoid contact; a runner whose forward progress has been stopped by a tackler; kickoff or punt returners while the ball is in the air; kickers or punters during a kick or a return; a quarterback during a change of possession; a player who receives a blindside block from a blocker moving toward his own end zone."

As you identified, the weakness of the Cover 3 are "flat routes" - would this extend to screens? Reading some discussions of these rules on twitter, someone proposed that these rules will make defending screens nearly impossible if you can't hit someone in the act of catching - wouldn't that make defending quick paterns close to the LOS even more difficult particularly for a Cover 3?

I think the rules leave a ton to be exploited.

I ran in to an issue last year in HS... The other team roll punted every time... If he was about to get tackled, while still behind the LOS, he acted like he was punting. We got flagged every time. I can see that happening with the pass rule.

I like the act of catching rule for safety, but as a coach, I think its going to take away a ton from the defense.

I disagree that defending screens will become a lot different, though. How often do you see someone get popped while in the act of catching a screen... Rare, if ever. When I say screen I mean a 2-screen (tailback) or a bubble screen or even a quick screen. They all occur behind the LOS.

The quick patterns near the LOS may mean that the flat defenders have to cheat a bit, which means they'll have to do it more often in man coverage as well. This could open the run game...

I don't know... It should be interesting to see. Truth be told, no one will know until it happens... But man, would I like to see the defense get some kind of rule change to their advantage.

What are the major differences between Cover 2 and Cover 3? More man to zone? I don't like zone defenses. It just seems to hamper a players natural strengths/instincts.

Spoken like a true novice I admit, but hey, if you don't know, ask someone who does

What are the major differences between Cover 2 and Cover 3? More man to zone? I don't like zone defenses. It just seems to hamper a players natural strengths/instincts.

Spoken like a true novice I admit, but hey, if you don't know, ask someone who does

Well, some people are actually much better in zone coverage. If you ask me, I'm more of a fan of zone. It helps guys out and doesn't leave anyone on an island. That said, if I had two shutdown corners and some decent coverage backers, I'd like man much more.

To be very vanilla, cover 2 is 2 deep safeties (strong safety, free safety) they play deep halves. Cover 3 has three deep guys (FS, Corner, Corner) playing thirds... Hence the "2" and "3" in the names of the coverages.

In cover 2, the corners will be playing the flats, in cover 3, they are bailing to deep thirds.

In cover 2 and 3 the SAM, and WILL have hok to curl zones. In cover 3 they have curls to flats.

The MIKE has roughly the same responsibility.

In cover 2, the weakness is a bit deeper than that of the cover 3. The cover 3 can be exposed into the flats... In cover 2, the flats are covered well by the corners. So any combo route that sends a receiver to the flat with a curl or a deeper out behind it is very difficult to defend in the cover 2.

The deep seam in cover two is towards the middle of the safeties.

Thanks Amigo. Isn't the Cover 3 essentially better? It seems whenever we played 2, all teams had to do was go down the middle and kill us, which they did regularly if memory serves. It seems to take a bit more finesse I suppose to do the same with the 3.

I think the rules leave a ton to be exploited.

I ran in to an issue last year in HS... The other team roll punted every time... If he was about to get tackled, while still behind the LOS, he acted like he was punting. We got flagged every time. I can see that happening with the pass rule.

I like the act of catching rule for safety, but as a coach, I think its going to take away a ton from the defense.

I disagree that defending screens will become a lot different, though. How often do you see someone get popped while in the act of catching a screen... Rare, if ever. When I say screen I mean a 2-screen (tailback) or a bubble screen or even a quick screen. They all occur behind the LOS.

The quick patterns near the LOS may mean that the flat defenders have to cheat a bit, which means they'll have to do it more often in man coverage as well. This could open the run game...

I don't know... It should be interesting to see. Truth be told, no one will know until it happens... But man, would I like to see the defense get some kind of rule change to their advantage.

I wouldn't be surprised if this rule change does not do what Al Davis et al thought the rule changes they thought would open up the deep game when they pushed the rules that made the quick pass game the weapon it is today.

Thanks Amigo. Isn't the Cover 3 essentially better? It seems whenever we played 2, all teams had to do was go down the middle and kill us, which they did regularly if memory serves. It seems to take a bit more finesse I suppose to do the same with the 3.

It depends on your strengths... It's like saying the zone rushing scheme is better than a power running scheme when really its dependent on your skill set as a team.

I like the cover 3 because we can roll Landry up into the box.

It depends on your strengths... It's like saying the zone rushing scheme is better than a power running scheme when really its dependent on your skill set as a team.

Yeah, I suppose at the end of the day that's what it all boils down to. Skill set-matchups

What are the major differences between Cover 2 and Cover 3? More man to zone? I don't like zone defenses. It just seems to hamper a players natural strengths/instincts.

Spoken like a true novice I admit, but hey, if you don't know, ask someone who does

To put it as simply as possible, the field is split into deep thirds in the Cover 3 (three defenders playing zone coverage over the top) and deep halves in a Cover 2 (only two defenders in a zone over the top). Who actually falls back into deep coverage depends on individual play design, although most of the time people will talk about both safeties covering deep in a Cover 2 and both corners and a safety in the Cover 3. A Cover 3 lends itself more to zone coverage for every defender than a Cover 2 does. Following suit you also have a Cover 1 (one defender in a zone over the top) and Cover 0 (no defender playing a zone over the top), which are more often associated with man coverage.

Just to pull up a few rough diagrams from one of my old threads for illustrative purposes...

3-4 Cover 3 Zone:

3-4 Cover 2 Zone:

You should notice that the gaps between defenders and "soft spots" in the zone are slightly different in each play.

Just to pull up a few rough diagrams from one of my old threads for illustrative purposes...

3-4 Cover 3 Zone:

3-4 Cover 2 Zone:

You should notice that the gaps between defenders and "soft spots" in the zone are slightly different in each play.

Thanks EA. Those diagrams were very helpful with regard to player responsibility.

Haven't read the thread yet, but when I saw the title "Chalk Talk", I got ridiculously excited. Thanks so much for these threads!

Yeah, I suppose at the end of the day that's what it all boils down to. Skill set-matchups

I think you're right to question the value of zone coverages in the NFL. I start with two major objections:

1) Since NFL QBs don't run much, the defense doesn't ordinarily have to assign a man to cover him. So, the D starts out virtually playing 11 on 10. When the DC puts his troops into a zone, he hands that man-advantage back to the OC, who can overload a zone, causing defenders in other zones to become spectators; and

2) Zone assignments are more complicated than man-coverage. Eleven players will defend 1,000 plays during the course of an NFL season. That's 11,000 opportunities to miss assignments per team per year.

Don't quit so easily, CB.

I think you're right to question the value of zone coverages in the NFL. I start with two major objections:

1) Since NFL QBs don't run much, the defense doesn't ordinarily have to assign a man to cover him. So, the D starts out virtually playing 11 on 10. When the DC puts his troops into a zone, he hands that man-advantage back to the OC, who can overload a zone, causing defenders in other zones to become spectators; and

You don't assign a man to cover a QB because he isn't a receiver, not because he isn't a threat to run. :pfft:

That man advantage still exists regardless of whether you play man or zone. The only difference is how it manifests itself. You could also make the case that the advantage is closer to an 11 on 9 because an entire offensive line will usually have its hands full with only four defenders.

2) Zone assignments are more complicated than man-coverage. Eleven players will defend 1,000 plays during the course of an NFL season. That's 11,000 opportunities to miss assignments per team.

Zone coverages are also less straightforward for a QB to read. You can personally dislike zone coverage if you wish but it is an important part of the game today.

Don't quit so easily, CB.

I think you're right to question the value of zone coverages in the NFL. I start with two major objections:

1) Since NFL QBs don't run much, the defense doesn't ordinarily have to assign a man to cover him. So, the D starts out virtually playing 11 on 10. When the DC puts his troops into a zone, he hands that man-advantage back to the OC, who can overload a zone, causing defenders in other zones to become spectators; and

Why would a man need to cover a QB? Coverage responsibilities and run responsibilities are two entirely different things. Furthermore a MIKE, or SAM, or WILL or whoever can effectively spy a quarterback while the rest of the team runs a zone coverage behind him.

2) Zone assignments are more complicated than man-coverage. Eleven players will defend 1,000 plays during the course of an NFL season. That's 11,000 opportunities to miss assignments per team per year.

Every effective team uses both. Zone assignments are more complicated than man, but they also provide help and don't put guys in one vs. one match ups that if they make a single footwork mistake they're beaten.

You don't assign a man to cover a QB because he isn't a receiver, not because he isn't a threat to run. :pfft:

Regardless, that man advantage still exists regardless of whether you play man or zone. The only difference is how it manifests itself.

Zone coverages are also less straightforward for a QB to read.

You can personally dislike zone coverage if you wish but it is an important part of the game today.

It depends on your strengths... It's like saying the zone rushing scheme is better than a power running scheme when really its dependent on your skill set as a team.

I like the cover 3 because we can roll Landry up into the box.

If we could handle it (I don't think we can, but still) I would honestly prefer a Cover 1. I prefer man coverage over zone, but that's just me.

If we could handle it (I don't think we can, but still) I would honestly prefer a Cover 1. I prefer man coverage over zone, but that's just me.

We'd be erasing DeAngelo Hall's impact on the game. He failed when playing man in Oakland. He's a zone corner.

How it manifests itself is the whole point. As I said, it allows the OC to take back the manpower advantage.

This is a chess game, Oldfan. The OC can find creative ways to take back the man advantage but the DC can also find ways to foil the OC's plans.

The question CB raised, and I follow up on is: Should it be a part of today's game?

I would say that zone-based defenses add a level of complexity and depth to the game that man coverage cannot. As such, I can't see why it shouldn't be part of today's game.

We'd be erasing DeAngelo Hall's impact on the game. He failed when playing man in Oakland. He's a zone corner.

That would also hurt Landry, who has never been a particularly stellar man cover safety.

Why would a man need to cover a QB?

Every effective team uses both. Zone assignments are more complicated than man, but they also provide help and don't put guys in one vs. one match ups that if they make a single footwork mistake they're beaten.

On most NFL teams, that's a big and fast WR. How many times have you seen our opponent's best receiver running free, completely uncovered, because a Skins defender missed an assignment? How did Andre Johnson end up single-covered by Reed Doughty last season?