3-Deep Coverage: Adjustments and Variations

Bumped. GO BRUINS. -N

Previous: 3-Deep Coverage: Basics, 3-Deep Coverage: Keys, 3-Deep Coverage: Technique

This should be the last installment on the 3-deep system. If you read and understood the other three parts, you should have a good idea of the basic system, philosophy, and technique used to cover the field. But to summarize:

1. Deep zones divided into thirds with players also covering underneath
2. Defend the field inside-out - protect the middle
3. Weak against 4-verticals, seam routes, a lot of crossing routes, and in the flats
4. Defenders will use pattern-read principles to figure out the most dangerous threat to their zone

If you are a 3-deep team you can't run the same thing over and over. So in this last part, I'll show some of the ways you can change things up to present the offense with different looks while still using this framework. NCAA regs put pretty strict limits on practice time - even HS coaches have more time to work with players - so the more multiple you can be while still using the same technique, the better. You can move guys around and swap assignments among positions, but it's all still the same system and based on the same technique.

Of course, none of this matters if you can't get the basic fundamentals down - pursuit, tackling, block destruction, and coverage. Below are some cut-ups of basic 3-deep covered in the past 3 posts - see if you can spot where the breakdowns occur on the plays where the offense has success against our defense.

Rotating Coverage

The most common way to change up 3-deep is to rotate the coverage - leave one CB in the flat, playing underneath coverage/force defender and shift the safeties over top of him.

The CB becomes the force player to the left side, responsible for the flats, and the SS drops deep behind him - this is called "Cloud" force (Sky = safety force, Buzz = backer force, Cloud = corner force). Putting the CB in the flat is a good way to stop the offense from picking on you in the flats. The bonus is that if you run 2-deep (and we do), your players are probably already familiar with this technique.

I clipped the video of ATV's pick against Arizona State where he played a cloud technique with Rahim Moore playing the deep zone over top. If you pay attention to ATV's eyes you can figure out how he's playing. He looks at the QB, looking for run/pass, then eyes go to the #1 WR, who goes vertical, so he gains depth to wall off the quick throw and his eyes go to #2. Slot WR doesn't threaten the flat and ATV plays the QB. 

Not sure if the pass was meant for the slot and really off-target, or if the #1 WR and the QB weren't on the same page/read the coverage differently, but either way the throw was terrible and an easy pick-six.

Trips Adjustments

If you watch the first wide-angle live shot of ATV's pick above, you can see that it was a 3-man rush with 3-deep and 5 underneath defenders (a DL drops off into coverage). Notice that Sheldon Price at the top of the screen doesn't play the same technique as ATV - he turns into the WR and runs with him downfield as if he's playing man, not zone. ASU lined up with 2 WR to the left and 3 to the right (known as trips).

Against trips, you'll see 3 vertical routes flooding a side as well as the bubble screen. Below is a fairly common way to defend trips out of 3-deep with the coverage rolled towards the trips side, becoming 1/4, 1/4, 1/2. The 1/2's corner on the backside is essentially in man coverage, and this appears to be what Sheldon Price did on this play. 

You have 2 DBs responsible for half of the field to the trips side, as well as a flat defender to play outside run force against the bubble screen and short routes, and the rest of the underneath zones shift towards the trips side. Backside you'll usually have some kind of solo call to put the CB man to man on the solo WR since there are no other vertical threats.

Blitzing

By far, the most common zone coverage behind a blitz is 3-deep. Generally you will see 3 deep and 3 underneath, known as a fire zone blitz.There's already a great explanation of the fire zone's workings here and several others if you do some googling, so if you're really interested in the nuts and bolts check out that site. I'll just summarize and answer questions in the comments. 

via Brophyfootball

1. 3-deep shell, using the same technique
2. You'll blitz two LBs and slant the DL away from the blitz - LBs loop in behind the DL.
3. Backside DE will drop off and play a SCIF technique - seam, curl, flat
4. Safety that doesn't drop deep will play SCIF to the other side
5. LB that doesn't blitz will play over the middle hole

You want the OL to shift with the DL, hopefully opening up a gap for the blitzing LBs. It works best against some kind of slide/gap/combo protection where some or all linemen slide a certain direction, and the blitz loops around and comes through the gaps they slide away from. On the backside, a rusher will drop off and play coverage.

Since you are only rushing 5, it's not about bringing more guys than the offense can block - it's about bringing more guys to a certain area that the offense can block. You can get guys with a free path to the QB with only committing 5 rushers and playing 6 in coverage as long as you have some OL dealing with multiple rushers and other OL blocking air.

Coverage-wise, the 3 underneath players are almost playing man coverage on #2 to both sides and #3, since there are only 3 underneath instead of 4. They are using the same pattern-reading principle except that they need to aggressively protect the seams. You want the QB to see the blitz and throw that way without seeing the SS dropping down.

There are a many different combinations you can do with this framework - the parts are interchangable as long as your players know the technique. You can blitz a CB and a LB, rotate the deep shell over, and slant the line away from the blitz. Or you can blitz the SS, and use the SLB as the SCIF player. Or you can blitz WLB and MLB up the gut, fan the DL outside, and use SLB/SS/DE as the underneath players. If you run a lot of 3-deep, then all of your safeties and OLBs should be able to play this role, as no matter what you do up front, you're still running 3 deep/3 underneath behind it.

See below for a few clips of UCLA's defense running the fire zone. For more, check here, here, here, here, and here. The blitzes don't all come from the same place, but there is generally 5 man pressure with some kind of stunt, loop, and/or slant, with 3-deep, 3-underneath (some of the clips show them sending 6, with 3-2 coverage, but same principles) using the technique above.