Once
again, Cal's 2016 defense is historically bad and people want
answers. I don't have them (if I did I'd be collecting half a
million a year and saving Sonny's job), but there are a few things
that can be added to the discussion that might be helpful for
thinking about what we're watching week-in and week-out.
The
biggest questions that people have are based around coverage. There
seems to be a solid consensus that goes something like this: Art
Kaufman is worried that our DB's will get burned if we play
aggressive coverage schemes, and so we play off-coverage and don't
put enough guys in the box, which also limits us in the pass rush.
As a result, not only do we get killed in the run game, but we give
up a ton of passing yards with a “Bend But Don't Break” coverage
strategy. If we're going to get killed in the passing game as it is,
why not play more aggressively with the DB's, load up the box, and
get after the RB/QB?
The
most egregious case of this came in the Oregon State game. Oregon
State's offense is bad, and their passing game is even worse. Their
rushing offense is the only thing that they have going for them, so
if ever there were a game to play aggressively in coverage and dare
them to beat us with the pass, this was it. So what happened?
To get
into this, I'm going to look at three of the coverages that we used
throughout the game and, most importantly, at the way that these
calls impacted the run game. My goal isn't to argue that we should
have played more of any one call in particular, or to excuse the fact
that we couldn't come up with answers, but rather to add some
additional considerations to the discussions that we're having now as
a fan base. In particular, I want to break down the false dichotomy
between (1) playing deep coverage but conceding the run, and (2)
playing tight coverage and being aggressive against the run. In
actuality, every coverage is vulnerable to certain passes, and every
front is vulnerable to certain runs. Our problem isn't that we were
playing too much of one coverage, but that we couldn't find a
defensive call that could stop the combination
of plays that Oregon State was throwing at us. Every coach and fan
in the country can come up with a call to stop any one specific play,
but DC's don't have to stop individual plays, they have to stop
complete offenses. If we want to understand why the defense is
struggling, then we need to look at how offensive and defensive
systems work as complete entities.
Cover-1:
Cover-1
(man coverage with a FS deep) is probably the coverage that fans
would most like to see against an offense like Oregon State's:
This
is a man coverage, and so you can press any of the WR's that you want
in order to disrupt the timing of routes and contest the short stuff.
This makes it good against a team that probably can't shred you
deep. Cover-1 also has a FS playing deep centerfield, so if one of
your guys does get beat, it's not an automatic TD. If you absolutely
must double-cover a WR, then that FS can also bracket him as the
second player in that double team, so even though it's a man
coverage, you don't automatically have to concede your worst matchup.
Most
importantly, Cover-1 will let the defense play with one more box
defender than the offense can block. In the diagram above, we see
that the offense is in a 2x2 spread formation with four WR's split
out wide. Since this is a man coverage, the defense will split out
four DB's to cover those four receivers and then, since it's Cover-1,
they will play with a FS deep. This means that a total of five
defenders are playing outside of the box. This leaves the defense
with six players to defend the run. Those six players are going up
against only five blockers (the OL), which gives the defense a +1
advantage against the run. No matter what the offense does, there
will be one guy in the box that they can't block. To put that
another way, when the offense has five blockers, they create six
gaps. In Cover-1, the defense has a player to fill all six of those
gaps:
As
long as those gaps stay stationary, we should be in good shape to
defend the run. This is where OSU's most dangerous play came in:
This
was one of OSU's most common run plays in our game. It's a variation
of a sweep that has the C and backside OT pulling to the playside
edge (to the left side, in this diagram).
This
play is difficult to defend because it takes the six gaps that we saw
above and it moves them around. To understand this, let's look at
how the gaps are distributed before the snap. We'll focus
specifically on the LG:
As
we can see here, before the snap there are two gaps to the left of
the LG (the red numbers), and four gaps to his right (the green
numbers). When OSU pulls the C and RT, however, this arrangement
changes:
By
bringing two additional blockers to the left edge, the offense now
has four gaps outside of the LG. The difficulty for the defense
comes in filling those four gaps. We have six players in the box
here, but three of our DL are going to be unable to get across the
formation to fill outside of the LG:
Let's
start from the right side of the diagram. As drawn here, the DE to
the offense's right side has to stay wide in case the QB pulls the
ball and keeps it (as he did a few times in this game). Next to him,
the DT is going to get sealed off by the RG, who has good leverage to
block him from crossing the formation. Similarly, the NT is going to
be sealed off by the LG. That leaves only three box defenders to
fill the four gaps that this play creates outside of the LG:
Because
all of our DB's are in man coverage, we can't rely on any of them
adding numbers against the run. They have to stay with their
receivers, and so are susceptible to getting blocked or run-off:
The
critical block here is the block of the LT on the WLB, which is
indicated by the red line. If the LT is able to keep the WLB from
coming across the formation, then there will be only two defenders
(the SLB and the DE) to fill three gaps outside of the LT. The RB
will read his blocks and pick whichever gap is open.
If
we want to slow this down, then we need our DE to read that the LT is
stepping down inside, and we need him to get hands on him and wash
him down the line to keep him from getting to the second level:
In
this diagram, the DE reads that the LT is stepping down inside, and
obstructs his path to the WLB. He pushes the LT down into the LG to
close the gap between them, and frees up the WLB to chase the pulling
linemen across the formation. Now the DE is in the gap outside the
LT, the WLB fills outside of the pulling C, and the SLB fills outside
of the pulling RT. In this hypothetical scenario (I don't think that
we ever actually did it, at least not cleanly), we've regained gap
integrity.
If
the DE can't fulfill this responsibility, however, or if the WLB
doesn't react quickly enough to get across the formation, then this
play will be very successful against us. Here, for example, is OSU's
long TD to start the second half:
The
SLB fills the outside gap on the edge, as he should, but the DE
doesn't get much contact on the LT, and the WLB doesn't get over the top of that block. The LT seals off the WLB, the RB
takes the open gap between the two pulling linemen, and all of the
sudden we have a converted QB coming downhill to try and tackle a
235-pound RB. 80 yards later and we're down 24-10. This kind of
play is going to make it hard for us to run Cover-1.
Cover-4
Benefits:
If
our DE's can't keep the OL off of our LB's, or if our LB's can't
react quickly enough to take advantage of the time that their DE's
buy them, then we need to make a call that gets an extra defender to
the playside. To do this, we used our base Cover-4:
This
coverage makes the CB's and safeties responsible for the four WR's
deep. The key for the run game here is the NB (on the left side of the diagram), who becomes our
seventh defender against the run. He's not responsible for the H
receiver on anything deep, because the FS is over the top. This
means that, in this coverage, the NB only has to cover that H
receiver on inside-breaking routes like slants:
If
the LT gets straight up to the WLB it doesn't matter, because we have
three other defenders (the DE, SLB, and NB) ready to fill the three
gaps outside of the LT. To introduce a term that's worth knowing, by changing our
coverage we've changed our run
support pattern.
By playing the more “conservative” Cover-4 instead of the
aggressive man coverage (Cover-1), we can actually get more defenders
involved against the run and fit well against OSU's most dangerous
play.
Cover-4
Problems:
If
Cover-4 had been able to shut down OSU's offense, then we would've
won the game easily. Although it could get us good numbers against
the particular sweep play that we've seen above, there were other
things that gave us trouble in both the run and pass game.
Above
we saw that the appeal of Cover-4 was that it let us get a NB
involved as an extra defender against the run on the edge. This run
responsibility could also cause problems in the passing game,
however. Here's one easy completion:
When
you have to rely on LB's/NB's coming from outside to seal the edge
against the run, then you're putting those players into a situation
with lots of potential run/pass conflict. A run/pass conflict means
that a player's responsibilities against the run and against the pass
require him to go in two different directions. This puts that player
in a tough spot, and requires him to make perfect reads and
reactions. On this particular play, we see a nice playcall by OSU.
They're going with a run fake, and using a pulling RG to seal the
left edge of their pass protection. This all makes the play look a
lot like the run plays that we're so worried about defending. To the
left of the diagram, our SLB is responsible for setting the edge
against any pulling lineman in the run game, and so he flies up to
maintain position outside of the RG. Against the pass, however, he's
supposed to drop and cut any inside routes by the Z receiver (the
inside-most receiver to the three-receiver side). When OSU goes with
the run fake, the SLB comes up to hold the edge against the pulling
RG. This takes him right out of the area that the Z receiver is
running his slant into, and OSU gets an easy completion for a nice
gain on first down.
One
persistent problem that also sank our ability to play Cover-4 was a
susceptibility to motion, including on jet motion. Here's OSU's first offensive
play of the game:
For this play, focus on the gap
outside of the Y receiver (the inside WR on the right side of the
diagram). On this play, OSU is going with a shovel pass to the H
receiver on jet motion. The Y receiver is cracking back on the WLB
to try and set the edge for the sweep. When the SS sees that Y
receiver crack blocking, it's going to be his job to come down and take
away the gap outside of Y in order to maintain the edge. The WLB
fights through his crack block, however, and so also ends up outside of
that Y receiver. This gives us the SS and WLB in the same outside
gap, but no one inside of Y. This opens up a big inside lane for the
sweep by H. This is ultimately a discipline/mental problem, and
results from overpursuit.
This motion also caused problems in
the passing game. Here's the pre-snap look for a conversion that OSU
picked up on 3rd
and 4:
On this play, we see the
off-coverage by the CB's. It's easy to blame this off technique when
they give up the completion, but it's a lot more complicated than
that.
OSU starts out in a 2x2 formation,
and then motions the Y receiver across on jet sweep motion. We're in
3-3 personnel, and our WLB is lined up over the Y receiver pre-snap.
When Y goes in motion, that WLB is going to auto-check to a blitz:
This is surely a coached adjustment
to motion, and puts him in unblocked pursuit against any run to the
left. Meanwhile, to the left side of the diagram, the FS is rocking
down to cover the Y receiver on the jet sweep or bubble screen, which
is fine:
All of this motion catches the eye
of our SS, however, which is one part of the problem (although the SS
isn't necessarily the one at fault here, as we'll see below):
It's hard to tell if this was the
right or wrong reaction within this coverage. Either way, it becomes
a problem because OSU is running a slant route right into the void
that that SS is vacating, and yes, because the CB is playing over the
top, he's not in a good position to make a play on this ball:
The CB shouldn't be the only player
defending this slant, however. In a zone coverage like this, the MLB
should be cutting the slant, at least initially:
This is, in fact, the MLB's initial
reaction, but the problem is that the RB is also releasing into the
flat. This pulls the MLB wide away from the slant, allowing the easy
completion:
I don't know what the specific
Cover-4 variant was on this play, but the one thing that seems
certain is that someone missed an adjustment. There are a bunch of
different plausible sets of rules that could've covered this. First,
the SS could've been assigned to “rob” under the outside
receiver (4-Robber), which would have freed up the MLB to widen with the RB:
If this is what the coverage was
supposed to be, then the SS missed his assignment and got caught
chasing the jet sweep instead of robbing under Z. Here's another
set of rules (4-Read) that could've covered this:
Here, the CB is responsible for
covering the RB in the flat, and passes off the slant route to the
MLB with the SS deep.
Here's one final set of rules that
could've covered this:
On this coverage, the WLB is playing
a “peel” technique. When the RB releases to his side, he stops
his blitz and chases him to the flat. This frees up the CB and MLB
to bracket the slant route, and would allow the SS to rotate toward
the jet motion as he did.
Any of these Cover-4 variants
could've taken care of this concept, and my guess is that one of
these is what we should've checked into after the motion. If this is correct, then with
the jet sweep motion someone missed their adjustment, causing our
underneath coverage to be overextended. Ultimately, I think that we
weren't ready for the RB to release out of the backfield as the
second receiver to the right, which was the ultimate source of the
confusion.
Cover-0:
In
the fourth quarter, we committed to playing Cover-0 (man coverage
with no deep safety). This let us get seven defenders in the box
against OSU's five blockers:
It's
going to be hard to run the ball against this front, and indeed this
was the only way that we were truly able to stop OSU's run game. It
was the fourth quarter and OSU had a lead, and so we weren't seeing
the same playcalling that we would've seen if we'd gone to this
coverage earlier, but there are some indications of what would've
happened if we'd tried to base out of this coverage:
This
is a 3rd
and 4 play. Because Cover-0 is a man coverage, each DB has to take
his man wherever he goes. OSU makes this difficult on the left side
of the diagram by running a curl/flat combination against our CB and
SS. The H receiver is releasing immediately to the flat, and so the
SS would have to get a great outside jump to make a play on the ball.
It's tough to see this in a 2-dimensional picture, but his most
direct path to do this is blocked by the route of the X receiver.
This sets a natural pick, and springs H open by enough to pick up the
first down.
Discussion:
I
started the schematic part of this post talking about Cover-1, but we
actually started the first quarter playing our base Cover-4. One
disconcerting part of the game was our difficulty in dealing with
motion and changing gap assignments in this coverage, as discussed
above. You can blame this on coaching, experience, or both (with
this last option being the most likely). The one thing I probably
wouldn't blame it on is recruiting or the players themselves. When
you're playing a lot of juniors and seniors, you don't want to see
this many problems. It's clear that OSU had a good gameplan in
place for what we were going to run, and they got a ton of mileage
out of relatively few plays. This drove us into Cover-1 as a
switchup starting in the second quarter, and we tried to mix this up
with Cover-4 (along with some Cover-3) for the two middle quarters.
For the reasons that I've gone through here, we couldn't get what we
needed from our front-6 when we played Cover-1 (again because of an
issue with reading blocks and reacting to them correctly), and so
going with this more aggressive man coverage actually weakened our
ability to defend the run on the edge and gave up some big yardage on
critical plays. With time running down in the fourth quarter,
everyone knew that Cover-0 was the only call that had any hope of
stopping the run and saving some clock for our offense, and so it was
easy for OSU to call up a few quick passes specifically designed to
beat it.
The
real key here is that we weren't running any of our defensive calls
very well (we had no obvious assignment/execution issues in Cover-0,
but we also didn't play many snaps in it). If you don't run your
plays well, then changing the playcall just swaps out one unsound
defense for another. You can try to disguise and blitz like crazy to
take the offense by surprise in this context, but remember: blitzes
have their own coverage assignments, checks, adjustments, etc. If
you can't manage those things in your base coverage, then you
probably won't be good at your exotic blitz assignments either. At
that point, you just have ASU's bad defense instead of our bad
defense. What we really need is better teaching and preparation
throughout the defense, both in installing the coverages themselves
and then in teaching the gameplan. That's something that comes from
the entire coaching staff's collaboration, starting in spring ball
and running through the end of the season, year after year.
For more discussion/questions, check out the thread for this post on BI: http://bearinsider.com/forums/showthread.php?104464-Bear-Raid-Breakdown-Cal-Defense-vs-OSU-2016
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