Thursday, October 8, 2009

Nick Saban: Middle of the Field Safety Coverage Principles (part III - Cover 1)

Cover 1

The simplest and best defense in football is man-free coverage.
It covers everything, it stuffs the run, and it defends the middle of the field.
It’s the #1 coverage in pro ball ....basically because you can’t get away with playing Cover 3.

Just like it sounds, man-free coverage is man-to-man defense with a free safety in the deep hole (and a linebacker in the shallow hole). Players simply line up and play the respective man across from them.
  1. Corners always take the first receiver outside (and use the MOF divider just like in C3)
  2. The Strong Safety displaces to the second receiver
  3. The Mike and Sam play the backs respectively (Sam has first back out strong / Mike has third back)
  4. The Will takes the first back out weak or the second receiver weak.
As can be found on page 167 of the LSU playbook, where it explains Cover 1 assignments and adjustments to each formation. The position-maintenance covered in the first section of this series plays a major part in funnelling receivers into the free safety / rat-in-the-hole help and eliminates duplication of effort. With man coverage, there becomes fewer opportunities for interceptions, but it increases the chances of an incompletion.
The main nuance of this coverage has to do with a challenging/conflicting assignments for the backers. Because the main thrust of the defense is to stop the run from the inside out and keeping the defenders playing fast, the premise is to keep the linebackers focused on the backs and TE. Saban uses an alert code (RAT) to prevent a potentially ‘coverage breaking’ route.
“RAT” is used to alert inside backers of the strong safety passing off his responsibility (tight end) to the inside linebackers. When the second receiver (tight end) stems inside (shallow), if the strong safety ran with him, he would be immediately vacating the perimeter (where the run game would likely be attacking) as well as running into the path of the (run game) pursuing linebackers (potential rub/pick). To quickly circumvent this hazard, when the tight end stems inside, the strong safety will declare/yell “RAT!”. “Rat” means a guy is coming into the funnel (is being funneled) and the remaining defender in the hole should cut/reroute and jump this receiver as he approaches.
This call accomplishes two things. First, it alerts the next backer over (Sam) that the strong safety will take his assigned man (first back out), and he should now adjust to the second back out strong. Secondly, it tells the Mike, who is the “rat in the hole” that he is going to have company soon (crossing tight end) and can jump this route as it comes.
This leaves the defense with +1 in the box, putting 3 linebackers on 2 (remaining) backs (see diagram below).
Because the 'rat' rules can be influenced by the first crosser, how does all this shake out in a real-time scenario? How is it all able to remain consistent and adjust to multi-level passing attacks? In the example below, the "shallow" or "NCAA" post/dig concept is utilized to attack the defensive coverage at 3 levels.
The corners obviously eliminate the outside receivers. Because the Y aligns inside the divider and is being funnelled into middle-of-the-field coverage, the strong safety aligns outside and his vertical positioning on him will be low-shoulder (see first post on position maintenance). This puts the strong safety in perfect position to deny the vertical-to-inside breaking dig route (with additional free safety sitting over the top in the deep hole to deny the dig and the post). Because the second receiver immediately takes an inside route (shallow), he is passed off to the rat-in-the-hole (S) who is looking to cut this receiver as he comes across the formation. The flow-side backer (M) to the side the back (F) releases takes his man into the flat/flare. Because the back is accounted for by the absolute 'funnel' rules (2 on 1), the W, who has released his shallow to the rat, is free to ROBOT (Roll and Run to find the seam/TE). Since he is not threatened by #1, #2, or #3 weak, the W, in this concept immediately bails to find the TE and rob the intermediate hole (ROBOT). This provides a 3-level-man-defense against this concept.
Obviously, walking out a linebacker on a weak receiver is not ideal, so what happens if a back motions out of the backfield or you are confronted with a true 1-back set? Do you displace a linebacker and leave yourself vulnerable to inside run? This isn't a good option, therefore a second alternative is offered ("1 Alert").
Because we just want linebackers matched up with backs and tight end, when confronted with a second receiver weak, “1 Alert” is used to precipitate an adjustment by the safeties. The defense will spin the safeties to the second receiver weak.
1 Alert means the tight end and remaining backs are taken by linebackers. All breaks are taken by safeties. To accommodate or adjust to this, the safeties will spin the coverage (typically away from the TE). Rather than walking out backers, the safeties adjust and the S takes the TE, leaving the M & W on the remaining back (2 on 1, as pictured below).
This essentially slides the backers away from the spin, leaving a 2 on 1 advantage with the linebackers on the remaining back. The linebacker to the side the back releases takes the back, the remaining linebacker becomes the rat in the hole. In summary;
  • “Funnel” when LBs have 3 on 2 versus the backs
  • “Alert” when LBs have 2 on 1 versus the backs.


JM said...

Well done on the 3-part series, man.

Now tackle Cover 7 from the same playbook.

jgordon1 said...

Brophy, Do the LB's read the backs vs the run too...or is it oline and then to the backs

Brophy said...

Flow to man is the backer read in C1
Flow + line in zone

Will said...

Brophy, great series. I will be visiting your blog often. Question: does the RAT call leave the defense open to a double-switch? For example in the diagram above where Y stems inside on the shallow and F has the shoot, the defense calls RAT to communicate the coverage switch. But what if Y runs a whip and F runs an angle? Will the defenders try to switch back to their original men or try to run past each other? This is a quicker version of what Ted Seay might call "dueling banjos."

brophy said...

Great question, but this isn't banjo coverage. This is straight man-to-man. This exchange simply aides a tricky stem (tight inside by #2), not serve as a rule for all defenders. Because of the position maintenance taught (see part I), the leverage the SLB would have on a whip by the TE would bring him back into the SLB (no advantage).

I'll take another look at the SC game and review the matchup against Lane Kiffin so to provide a competent breakdown of what is to come versus the SEC West super matchup on Nov 7th.

Anonymous said...

Does a good runner at QB change the cover progressions for the 3 on 2 or 2 on 1?

Never motion out LB if possible, the run front must remain intact.
Unless all they put to slot is a blocker like a true FB, or blocking TE, to lead a screen.