A new wave of NFL stars is on the horizon. Fast-paced, high-scoring offenses are popping up all over the league. Quarterbacks like Josh Allen and Lamar Jackson are spreading the field with their arms and legs. Everywhere you look it’s speed, speed, and more speed. What’s a defense gotta do to keep up? Well, put even more speed on the field, of course. Let’s examine what could be an exciting new trend!
Interpreting snap count data
To get a handle on what we’re about to explore, it’s beneficial to be able to quickly analyze snap counts. Doing so can give you a feel for what went down schematically without re-watching an entire game and taking notes. A simple method is to add up the percentages of every player in each position group. Let’s take a look at an “ideal” 4-3 defense, the philosophy the Buffalo Bills use.
This model chart assumes the team was in 4-3 the entire game to give us easy math. While there could be more than four players on the line, their total adds up to 400%. Now these days you’ll never see a chart end up looking like this, but the interpretation is that the Bills had four lineman, three linebackers, two safeties, and two cornerbacks on the field at all times. Alright, now let’s fill in a couple of those gray rows and make things a little harder.
The Buffalo Bills
You might recall that at the end of 2017, Buffalo Rumblings made a big ruckus about the Bills correcting their defensive woes by going heavy on the nickel defense. What this means is a shift to five defensive backs rather than the four the chart above shows. This approach puts more speed on the field, and worked well for the Bills to close that season. Here’s another chart.
Here we have two games’ worth of snap counts for the Bills, one for each of McDermott’s seasons. Starting on easy ground, note that in both games the Bills kept the safety counts to around 200%, which strongly suggests two safeties took every snap. Moving to corner, we see both are at 290% or above. So in addition to the normal two corners, a third was on the field nearly always. For that second game against Green Bay, the 292% for corners and 208% for safeties makes it highly likely the Bills spent the entire game using a nickel defense.
What does this mean for the other position groups? It appears that sometimes the Bills don’t have four lineman on the field, but that’s a half truth. For the Bills, Lorenzo Alexander fills in at defensive tackle but still gets listed as a linebacker. The stats don’t translate perfectly every time, however it is still half-true like I mentioned. A smaller, faster guy is on the field instead of a defensive tackle.
These two games stand out because they’re shockingly nickel heavy. While the league is trending this way, the data here shows that Buffalo isn’t really running a 4-3. Their base defense is nickel. Why don’t you hear much conversation about linebackers besides Matt Milano and Tremaine Edmunds? Because there’s not three true linebackers on the field at the same time all that often.
The last time the Bills faced the Patriots, Buffalo only managed twelve points and fewer than 300 yards of total offense. Three turnovers and an abysmal 2-of-12 third down conversions mean that New England had a good day on defense. Did they do something special? Time for another chart.
Starting from right to left, there appears to have been three corners on the field all game. That’s not exactly true, but for now we’ll say for certain that the Patriots took the extra corner concept a half-step further than Buffalo did in the two sample games. Moving left we see they also appear to have added an extra safety one-third of the time. So on average, the Patriots may as well have been in at least nickel the entire game, with one-third actually being a dime defense (defenses with six defensive backs instead of the five in a nickel).
One thing to note about the Patriots is that they run a hybrid defense that floats between 4-3 and 3-4 schemes. That helps explain that the defensive tackles appear to be losing more snaps than the linebackers to give extra time to the defensive backs. Let’s examine a couple plays from that game.
Believe it or not, despite the snap counts above, the Patriots did use some base defense with only four defensive backs. Helping inflate their defensive-back count, they ran a good chunk of plays using a quarter defense. This isn’t a term you see used a lot because it’s not a type of defense that’s used a lot. Going up the coin chain, a quarter defense uses seven defensive backs. Prevent defenses are often quarter or half-dollar. What makes the Patriots quarter defense odd is that it’s not a prevent model, with most of the players deep to avoid giving up a quick score. In the play above, look how fast Josh Allen is swarmed. The absurdly high number of defensive backs gives the entire Patriots defense oodles of closing speed. Unlike the time Allen schooled Kiko Alonso, there are several players faster than the quarterback above.
Here’s another play using quarter defense. Every defender is in a pretty normal spot, and this is in no way a prevent concept. With Buffalo shifting toward a group of faster receivers, the Patriots have plenty of speed to match it.
It was less than a thousand words ago we were remarking that the Bills were wacky for running such a nickel-heavy scheme. Now here we are with nickel seeming bland. The idea is still the same, match speed for speed.
With all this speed on the field, what would it look like if a team was willing to take their defense all the way to plaid? Thanks to the Chargers, we have an answer.
There were zero, none, zilch, no linebackers on the field at all for more than two-thirds of the time. The Chargers see the Patriots’ and Bills’ three-corner average and raise them TWO safeties. Based on data alone, the base defense the Chargers used to take down the Lamar Jackson-led Baltimore Ravens was a quarter defense. Usually reserved for stopping a Hail Mary attempt, the Chargers used it pretty much all game.
This is the first play of the game. The Chargers are using a quarter defense. There are no linebackers anywhere to be seen. Lamar Jackson, who is a pretty quick guy, has nowhere to run. Speaking of running, a power-running style should be able to counter a quarter defense you’d think. Let’s see what the Ravens did to try to counter all this speed from the Chargers.
Initially the Ravens look to have this blocked well. The Chargers have been well-prepared to roll out their new ludicrous-speed defense. Rather than have everyone immediately take on a block, the Chargers’ defenders are asked to do more read and react, allowing their speed to let them capitalize. A talented front four helps out a good deal too. The Ravens never truly countered. Even considering garbage time, the Ravens had their lowest amount in points, total yards, and rushing yards since Week 9.
So then, are these game anomalies or the hot new trend? In a league where teams love to copy one another, it’s a safe bet that smaller and faster defenses will begin to creep in elsewhere. Keep an eye on the defensive back ends throughout the playoffs and into next year as teams try to beat the running quarterbacks.