3-Deep Coverage: Keys

Previous: 3-Deep Coverage: Basics

Below are what I believe to be the most important keys of running a successful 3-deep coverage. These are mainly related to pass coverage - the only major keys in stopping the run are that the middle needs to be solid and that the force players cannot get beat outside, which is pretty much universal. 

Keys

1. The middle of the field has to be covered.

If you can't defend the middle of the field in 3-deep it will be a long day. The big picture is to defend "inside-out", which means you must be solid in the middle and push the offense outside. The ball travels further when the QB throws outside. 

A throw outside to the WR has to travel further than one to the TE over the middle. Longer distance = longer time = more time for you to get there. So you want to worry more about the slot receiver doing deep and cover the immediate vertical threat (see Key #2 below) before dealing with the WR to the far left on the bench route. Against this play (and I'll explain technique in another post), you'd want the CB squeezing the deep route with help from the FS to the inside, while the OLB to that side would be preventing the immediate throw to the slot and then sliding underneath the out route. As he is in the passing lane, the QB cannot fire a quick "bullet" pass. The only way he can hit the out is by putting some air under the ball and taking some velocity off the ball; this gives both the OLB and the CB time to react to the out route. 

No matter what, the defense can't give up easy passes over the middle. Any QB can hit a TE settling in a hole right in front of him, but its a lot harder to get the ball to that out route. The shaded area below shows the area that the deep middle defender has to cover - he has the most ground to work with, since he doesn't have the benefit of the sideline, and he needs help from the rest of the defense to get it done.

2. Protect the seams.

The seams (shaded area in the right image, just down the hash marks between the "seams" of the deep zones) are the weakest point in the coverage. In the diagram above, the slot WR is running down the seams, and this the biggest threat. The only play that can really hurt 3-deep is 4 vertical routes. Against 4-verts, the CBs should be able to hold their own with sideline help. However, the safety will be facing down two vertical threats and praying that he gets help from one of the underneath defenders. They need to re-route #2 and wall off any quick throw and keep these guys from running free down the seams.

3. Cover the deepest man.

You don't want to be breaking up the 3-yard passes to the shallow routes or the quick passes to the flats consistently. If you are jumping those, then you are playing too aggressively. If your underneath defenders keep jumping a 3-yard shallow cross, then you'll probably get a shallow cross with a 12-yard dig route over top of it the next time. Underneath defenders can't get sucked into playing short routes - they shouldn't be covering anything under 5 yards. They should be playing the 8 and 12 yard routes and rallying up to make the tackle on the short stuff. You just have to be disciplined and force the 3 or 4 yard throw and tackle well. Crossing routes at different levels often cause problems, because undisciplined players will "bite" on the short routes, giving up the deep completions. For example, the shallow cross series presents a few problems to 3-deep because undisciplined defenders jump the short routes, but you want to cover the post and the dig before dropping down to any of the short stuff.

In basic 3-deep, we will give up a 3-yard pass to the flat and work up to the tackle. Offenses will usually either use concepts that attack the seams or plays such as bubble screens that attack the flats to force a defense to adjust. However, there are ways for the defense to adjust to that as well and take away those quick passes to the flats which I will get to eventually.

Personnel

From those three keys you can probably figure out what you need in terms of personnel. As long as you can teach the system and technique then I feel that you can get by without exceptional talent (although that never hurts). I think that the deep middle defender and the curl/flat defenders have the most ground to cover and the toughest jobs. 

Safeties have to be versatile. We know what Rahim Moore can do, but last season we played both safety spots at deep middle and Tony Dye had roughly 1/3 of the snaps back there. The rest of the time, they were playing in the box. If you have a safety back there in deep middle, he has to have pretty good range and has to have a knack for chasing the ball down. Rahim Moore had at least two picks last year (UW and Temple) where he got from deep middle to the sideline just as the ball arrived - that's 2.5 seconds from middle of the field to sideline (roughly 25 yards, if you're running perpendicular to the sideline). When they're not in deep middle they will be force defenders/backside pursuit defenders and curl/flat, which means they must be disciplined and stout against the run and must make great reads in order to figure out where to go against the pass. In our scheme, we had the safeties sometimes drop between Akeem Ayers and Reggie Carter and play some hook/curl as well to mix things up.

The other difficult position to fill are the curl/flat defenders. Sometimes they will be the other safety and sometimes they will be an outside linebacker. We have another athlete in Akeem Ayers, who has plenty of talent, but needs to work on staying disciplined as a force defender. Glenn Love, who split time in this spot a little last season as a strong safety, is moving to linebacker, which isn't really that big a change technique-wise, so the shift makes sense and he should have a leg up on the competition. I think it also shows a lot of trust in Tony Dye, who struggled at times in 2009. Last year we had a senior in Kyle Bosworth who did well in the system, but next year we will have to break in some new guys. 

Other than those three positions (an exceptional defender who can play deep middle and two intelligent curl/flat defenders), I don't think that the system asks too much out of any one player. Not to say that the other positions don't matter - never hurts to have talent - but I think you will struggle if you do not get great play from these three positions as they are the most responsible for defending the middle of the field and the seams.

Next time I'll explain some of the techniques you use to make this all work, and then eventually I'll take a look at some of the flexibility you get within a 3-deep system while still using the same basic framework and techniques.

Next: 3-Deep Coverage: Technique