Friday, October 24, 2014

Film Review: Nebraska Schemed By Northwestern's Cover 4; Then Schemed Them Back

Northwestern threw a lot of cover 4 at Nebraska in an effort to get bodies down into the run game. One thing that Cover 4 allows is for the LBs to flow a bit more freely and quickly to the initial look, because the safety takes care of backside cutbacks. What we saw in the Nebraska vs Northwestern game was Northwestern initially having success bottling up Nebraska because of this. The safety crashing down from depth allows him to defend either the QB keep or the RB cutting back across the grain. Later on, however, we saw Nebraska adjust some of their play calls to take advantage of this scheme. In this post, we’ll look at just that.

Handling the Cutback
This is the very first offensive play of the game. Note that the H-back here will run the inside zone blocking scheme just as everyone else does and crash down on the defensive end. Here’s the general set up of the play from an offensive and defensive standpoint. Note that the boundary safety can creep down a bit because there isn’t really a vertical threat to his side (the H-back is inside the tackle box).

Armstrong sees the safety crashing down on what is essentially a scrape exchange between the DE and the safety, notice the DE getting his helmet playside of the H-back on the bottom of the screen. It is that key to Armstrong to give.

But because the safety is coming from depth, rather than a set point at the LOS, he has time on his path to read whether Armstrong is keeping or giving. By the time he reaches the LOS, he reads give and can squeeze the hole. The safety does a nice job squeezing the hole but not allowing the play to bounce outside, because you can see how absolutely everyone else on the defense committed to the original playside.

The safety makes the tackle for a two yard gain because holding down Abdullah is giving up a two yard gain, but that’s a really nice play by the safety. Also note that there is a pop pass option to Bell on the bottom of the screen, but with Northwestern mostly running Cover 4 that doesn’t come into play (you’re looking for something like Cover 3 with that pop pass, where a safety or LB have backside contain on what would be a scrape exchange equivalent, but the CB is bailing into a deep third at the snap; though, FWIW, the next play they came back to a short hitch to Bell as even in their quarters coverage Northwestern was a little bit nervous about getting beat over the top early).

Flowing to Inverted Veer
Two plays later, Nebraska comes back with an inverted veer into the boundary. Like speed option against Cover 4, most teams like to run this kind of play into the boundary because it is a bit more difficult for the boundary safety to fill the alley. Northwestern is again in Cover 4 on this initial alignment. Note that the boxed Northwestern player is the read defender.
Nebraska actually has a hat for a hat on this as the interior OL crushes the Northwestern DL, seemingly pancaking half of them. On top of that, the read defender takes himself out of the play by crashing hard inside. That partly because Nebraska hasn’t run a ton of inverted veer this year (compared to previous years, it’s been a lot less), instead opting for the zone read; but it also seems it’s because they are again going with a bit of the scrape exchange type theme to try to confuse Armstrong’s read. Armstrong gives though because that’s the correct thing to do (he’s been quite good with his run game reads this year) and Abdullah gets the ball. The slot receiver comes down on the OLB and pins him, leaving the safety coming from deep to be the one that has to clean everything up again.
Where Abdullah makes a mistake is that he continues to work toward the sideline. This is a bit tricky, because you need to get separation between the QB run and the RB run for the read portion to work, but rarely is the inverted veer a play that really attacks all the way to the edge, you typically cut up against flow. With Northwestern in a Cover 4, the safety won’t allow anyone outside of him on his charge up the field. But that’s fine, Nebraska has a hat for a hat and the rest of the play sealed inside. They also have a pulling OG that is scanning the field looking for the first off color jersey to block now that no one is working inside out to him. If Abdullah is patient, his OG can get into that block, kick out the safety, and this is a TD because the fast flow was sealed inside by the formation.

But he continues to bounce, flow can arrive, and he’s forced into the sideline for a minimal gain (because Abdullah doesn’t lose yardage).

Fast Flow Cuts Down Speed Option
One way Nebraska likes to attack this sort of formation is to run speed option into it. That tends to work because the read man is to the playside, or where the flow is going, so in some ways you can account for the fast flow. Here’s the set up.
[This is actually a really good example of why teams typically run speed option into the boundary, so I’m going to go on a bit of an aside. Notice how the boundary safety is working toward the middle of the field. That’s because on a pass play he is going to cover #3 (the TE) if he goes vertical. It’s a standard trips adjustment. Also, because you typically align more receivers where there is more room (in an effort to have spacing), you have a slot toward that side. That slot puts a safety in that alley and it puts an OLB in an apex position between the slot and the EMOL. That OLB is the read player, but there is flow on the backend to account for the speed option, and there are a lot of defenders to that side.

On the flip side, a speed option to the boundary is very easily blocked here. You read the DE, the OT has a great angle to work to the WILL. There isn’t even a defender between him in his man that he has to work around. Once after the DE, the only player that can make any play close to the LOS is the CB, who is blocked by the WR. A CB having to make a play in space is already a win for the offense, but a blocked CB having to make a play is a goldmine. With the boundary safety working over the top, he wouldn’t be able to even get there until late. A speed option into the boundary is likely 10 free yards.]

Anyway, because the DE is lined up in a 7 technique (inside shade on the TE), and the DE needs to be blocked because of the overhang OLB, that means the TE and OT need to combo to a fast flowing LB. That proves difficult as you might expect.
And here’s what Armstrong is looking at once he gets to his read point.
His read is flaring, so he keeps as he should, but there are two players in limited space square to the player they are responsible for. Armstrong manages to make a little bit out of this, but this isn’t a road to success.

Block the Backside with Counter Trey
Now, I’ll say up front that this isn’t the best example, because the play loses yardage. But I’m still going to use it because it stresses how the scheme is designed to work, and I’ll briefly get into why it doesn’t.

Here’s the initial set up. Note again that Nebraska has a three receivers to the field, one of which is a TE. That forces the boundary safety to motion to the center of the field late to deal with the threat of #3 working vertical. The intention is to get the LBs flowing with the RB, like on an inverted veer look.
Now, this can still be a read play, there is nothing that says otherwise, but it must be very clear in order to give. The QB is reading the DE toward running back flow, but he must also look through the DE to the LB level to ensure that they are making their proper reads on the counter trey and actually flowing away from the RB (basically, if the LBs are over reacting to the inverted veer look, the counter trey keep should be a big gain; if they actually make their reads properly and realize counter trey, the give should be a big gain). The LB to the short side is reading counter trey, but he isn’t being read a QB can’t read everyone; the LB to the wide side of the field is maintaining his relation to the RB though (and the DE is playing outside), so the read for Armstrong is to keep.
Now, Northwestern has been crashing their backside DE all day and effectively exchanging the outside responsibility. The pulling guard who will typically trap block that DE must understand this. Because the DE is crashing hard, it becomes very difficult to kick him out. The trapping OG must maintain a path tight to the butts of the rest of the OL and force the DE to work high and into the wash or take himself out of the play by committing up field. When the DE works back into the wash, rather than kicking him, the OG will scoop him and seal him inside, allowing the OT to pull and lead up to the LB and a bunch of clear grass for Armstrong.

But the OG doesn’t force the DE to work back into the wash, and his path has an incorrect aiming point (he aims to the OL side rather than at the upfield shoulder). At the last minute, the DE can shoot upfield and essentially wrong arm the pulling OT, thus taking out to blockers with one player and causing a pile up. On top of that, the playside LB is now clean.
And thus this play is doomed for a 4 yard loss, not because of scheme, design, or timing, but because the OL failed to execute in this situation.

Block the Safety, Break Tendency
It’s the 4th quarter and Nebraska has just run the same play (inside zone read) from the same formation and gotten the same exact result, with Abdullah cutting back into a crashing safety for a two yard gain. Here’s how they line up on the next play.
All day this has been inside zone read away from the RB alignment, which here means the RB will run to the wide side of the field. But Nebraska changes some things. First, note how the there is an inverted twins to the short side of the field. Many Cover 4 teams won’t apex their LB to the short side of the field, because the spacing is such that they can play the box and make it outside on a run, along with the alley fill by the safety. This means the up WR in the slot is able to block to the safety.

Secondly, Nebraska actually runs stretch to the boundary rather than inside zone to the field. That’s a nice break in tendency, but even if they ran the inside zone read and Abdullah cut back like he had all day, the result would have been the same, and it’s because of that slot receiver to the boundary. Here’s the play design.
Now, you’ll note that the playside OL can’t seal the Northwestern DL inside. That’s fine, it rarely works that way. But because Northwestern has flowed so fast playside all game, those DL can get washed out. The important thing is that the OL reaches the 2nd level LBs and seals them, and the slot receiver blocks the safety.
This leaves a huge gap for Abdullah and everyone to the play completely blocked. And here’s that receiver driving that safety as Abdullah runs by for a 50 yard gain. FWIW, that receiver lined up in the slot is TE Sam Cotton. Nebraska maintained their personnel, but a slight formation change popped the big run.


Northwestern utilized scheme to bottle up a lot of what Nebraska wanted to run as their base set of run plays. But typically when you scheme in a way to handle one thing so much, you leave yourself susceptible to something else. It took Nebraska a bit of time to find out how they could successfully attack Northwestern, even when scheming in ways that theoretically should (the counter trey). But against Northwestern’s fast flowing Cover 4 scheme, Nebraska was able to run into the boundary, with a slot receiver there to block the safety, and break tendency, and therefore bust a big play and make what was a tight game into a two possession game.

No comments:

Post a Comment