Originally posted by thl408:
NY can you paste me this article? Really interested in the quantitative stats here but I don't have a subscription.
https://www.pff.com/news/nfl-seth-galina-quarters-revolution-is-coming-nfl-offensive-schemes
The revolution is coming.
After a decade of living in a Cover 3 world, change is inevitable. As offenses start to figure out how to consistently beat the defense that most of the league is playing, defenses will have no choice but to adjust.
[Editor's Note: PFF's advanced statistics and player grades are powered by AWS machine learning capabilities.]
In an ideal world, the evolution of defense will be toward a purely man-coverage scheme — our guys against your guys. Though that's not always the best practice when your guys can't stick to their guys, and that has been true for however long the forward pass has been around.
Defenses have always needed a zone counterpart to their man-coverage schemes. The league went from the Cover 2/Tampa 2 defenses of the 2000s to the Cover 3 defenses of the 2010s, and now we might be on the precipice of the "Quarters" revolution in the NFL.
College football has unleashed the quarters revolution in response to the spread effect for almost two decades now, but it hasn't hit the NFL level at quite the extent.
Just in Big 12 conference games over the last two seasons, defenses ran quarters on 36% of passing snaps on first and second downs. You would have thought that number would have been higher in the 2005-15 period, as the Big 12 was popular for its quarters defense, but the conference has actually been at the forefront of shifting
away from quarters in recent years.
Still, that 36% number is much higher than the NFL's 19% of snaps in quarters coverage on early downs over the last six seasons. The lowest number of snaps in quarters came in 2015 (17.7%), while the highest over those six years was in 2016 (20.2%). There has neither been a big fluctuation nor a year-by-year increase.
While the league hasn't shown an incredible increase in usage over the past six seasons — I believe we would see a bigger increase if we had charting data pre-2014 — some individual teams have shown more quarters than others. In 2019, the Raiders, Vikings and Texans played over 30% of their defensive snaps in quarters on early downs, while Cover 3 holdovers such as the Falcons (via Dan Quinn's time in Seattle) and Cowboys (via Kris Richard's time in Seattle) make up the bottom two teams in usage.
We use early downs here because third-down coverages can get funky sometimes, and we want to see what teams are up to when they can't just sell out against the pass and have to worry about a run play being called.
I've previously written about how teams should be playing more two-high zone coveragesbecause individual teams do about as well stopping the run in two-high as they do in single-high. This article was about how defenses can stop the run with the extra box defender that single-high defenses afford. For this piece, however, we'll look at how NFL teams play quarters in the passing game and how it will have to evolve a bit to become more robust for increased usage.
In our current Cover 3 world, offenses have adapted to counter that zone defense. There have been 159 team seasons over the last five seasons where a team played over 25 passing snaps in Cover 3 on early downs, and 108 of them allowed a positive EPA per play mark over the season.
"Quarters" means there are four deep zone defenders, and it's why the name is mostly interchangeable with the term "Cover 4."
The cornerbacks and the two safeties are generally the four deep players. The two outside linebackers — for the purpose of this exercise, the nickelback is an outside linebacker, as he is the old Sam linebacker — are the flat defenders. The Mike linebacker is the middle hook player.
The four deep defenders are in red, the two flat defenders in yellow, the middle hook is green.
The litmus test to identify a quarters coverage is when an offense runs the "4 Verts" play. If four players cover the four vertical runners, then it's probably quarters. With that said, there is an almost infinite way that the defense can choose to distribute who covers whom. For the most part, NFL defenses do this in one way. This is where the evolution must occur, as the trendline for quarters starts to move upward. There need to be more answers.
The NFL loves to have their zone defenders be "spot droppers." This means the defender will get to his hustle and then look at the quarterback to break on a thrown pass. Some people call this "visioning the quarterback."
You can see in the above clip that the Minnesota Vikings are showing a classic two-high, 4-3 defense look and will end up playing a quarters coverage variant. Besides the flat defender on the bottom of the screen, everyone is opening up and looking at the quarterback before looking to break on the ball. The ball is forced to the flat area, which is where the defense wants the ball thrown.
Here (below) is another example, where every Panther drops into their zone and then visions the quarterback.
NFL teams have a couple of zone variants that they like to use often enough. The first is "palms," which is also known as "two-read" or just "trap." This tells the cornerback that if the slot receiver runs to an out-breaking pattern underneath a certain depth — this could be decided on a week-to-week basis — he is to jump that route from the outside in.
This (above) is a great example from former Raider Gareon Conley. He takes a couple of steps backward, but he breaks on the throw once he sees the Broncos receiver turn outside within 5 yards of the line of scrimmage. Even though the ball is caught, there is no chance for any yards after the catch up the sideline, which is what offenses want against Cover 4 teams.
Another technique quarters teams like to use is called "poach." Against trips formations, the safety who is to the one-receiver side will turn and look back to the three-receiver side and try to cut off any vertical-bending route to his side.
The San Francisco 49ers used this idea quite a bit against the Kansas City Chiefs in the Superbowl.
The "weak" safety turns and looks to the three-receiver side right on the snap and is in a position to jump the route that comes across the field.
I believe that the athletic ability and intelligence of the modern NFL defender allow pro defenses to get away with this all the time. Yes, they're dropping to their zone, but they can also react faster. The good ones also understand what route concepts they are likely to get in a given situation.
The defenders might be athletic and smart, but the quarterbacks on the other side — even the bad ones, if we're quite honest — are so good at finding the holes where defenders are not. Playing the coverage as a changeup and only doing it even 30% on the high end means teams can probably get away with this.
When the revolution happens, teams are going to need more ways to skin the cat — the results from what teams are currently doing to stick with the spot-dropping defense simply aren't good enough. Of the 142 team seasons where a defense played quarters on over 25 passing snaps on early downs, 100 allowed a positive EPA per play figure.
Defenses are going to have to start running more match-style zone defenses to keep up. Let's take a look at Nick Saban's Alabama defense for clues.
You can see the underneath defenders turn and find the receivers to cover. Watch the switch between the sam linebacker and the mike linebacker on the top when the running back flares out to the flat. The mike pushes the sam out to cover the running back while the mike sticks to the slot receiver. Contrast that to the Vikings-Falcons clip above. The same push happens, only the mike linebacker still zones off instead of sticking man-to-man.
This matching style is not seen that much in the NFL. In fact, the Panthers, who played the most quarters snaps against 2×2 formations on early downs last year, spot-dropped on all of them.
Match-style two-high defenses are certainly not a way to magically make completions disappear, but it does act as a fine changeup once teams start hitting that 40% quarters mark that should be coming within the next five seasons.
The positive of this type of defense is that everyone ends up covering someone — no defender ends up "covering grass," so to speak. The flipside is that you can find yourself with linebackers covering players who are much quicker than them, and you can bet NFL coaches don't see that as a winning business model.
The safeties also have to start at a lower depth, and you can see just how low both safeties are in the Alabama clip. Because the underneath defenders can get pulled away from the middle of the field, the safeties have to be able to sit and drive on intermediate in-breaking routes without underneath cover. Again, the NFL might not think that playing safeties that low against the world-class speed at the slot receiver position is a winning business model.
Just as Cover 3 defenses have evolved to include match defenses, so too must quarters looks. There are so many more match-quarters variants than there are Cover 3-match variants, so defenses can keep the offense at bay at least schematically.
The next evolution of defense is coming, and we are most likely only a few years from entering the quarters bubble. When we get there, teams must continually evolve to keep offenses guessing as to where exactly the individual defenders will end up based on the distribution of the receiver routes.
there's some clips but I can't post those
