What is Wrong (and Right) With the Eagles Defense

I didn’t post last week after the Cowboys game because I don’t want to be over-reactionary on a bad game (and because I also had a few vacation days away). There is so much justified focus on the Eagles defense after the first 4 games and I wanted to look into it deeper.

In prior posts, I looked at each of the defensive units and made the following points:

  • The Eagles have invested in DL but I’ve been worried on their run defense for a while. Over the past 5 years, the Eagles run defense was rated between 10-19 in the league with a noticeable regression in 2020.
    (See “Analytics of the Eagles DL Draft History” for more detail)
  • The Eagles well known underinvestment in LB has shown when looking at LB value vs. defensive DVOA. But one thing often overlooked is a lot of the value in the Eagles run defense up until 2019 came from Malcolm Jenkins who was effectively a LB (and a very good one). Once he left, the LBs became more exposed and the run defense took a hit.
    (See “Analytics of the Eagles LB Draft History” for more detail)
  • Howie’s biggest draft issue is undervaluing corner which is absolutely a premium position today (second to only quarterback). Gannon has shown to improve secondaries in MIN and IND, but he also had more talent there.
    (See “What Can We Expect from Gannon’s Scheme” for mote detail)

We are almost a quarter of the way through the 2021 season but with a new coaching staff, a lot still can and will change, but I am less concerned with the game-to-game swings and more concerned with the underlying performance and talent. And not much so far in 2021 has changed my views. Here are my top thoughts on the Eagles defense:

Teams are exposing our personnel weaknesses in the run game

I always have to caveat when I talk about the run game as the broader analytics community would never run because rushes have lower expected value than passes and are, in aggregate, negative EPA. And this is true as you would much rather be good against the pass than the run. But the Eagles run defense has crossed the line to being a problem.

The Eagles are allowing a positive EPA on rushes
They are one of only 10 defenses actually allowing a positive EPA per play (0.006) on opposing team rushes. Yes, passes have even greater value, but it is rare to allow a positive EPA on rushes.

The Eagles are allowing a lot of explosive runs
They are 27th in the league in number of explosive rushes allowed with 11 through 4 games. They are tied with the 49ers and only the Chiefs, Raiders, Cardinals, Texans, and Jets have allowed more. (This post isn’t about their offensive play calling but I am sure nobody missed that the 49ers and Chiefs are worse than the Eagles here but we still refused to run against both…)

Teams are exploiting the Eagles scheme and personnel on the outside
The Eagles defense is seeing a much higher percentage of outside runs than the league average, with almost half of rushes against them being wide, and giving up 0.207 EPA per play on outside runs, ranked 26th in the league (for a defense, a lower EPA is better). As a point of reference, the league average EPA per pass is 0.192. Above I said the analytics community hates runs because they have negative EPA and always less value than passes but the Eagles are allowing more value on outside runs than the average league pass.

The Eagles are also 30th in the league with an average depth of tackle of 5.37 yards. While our EDGEs Barnett and Sweat are our top two highest graded run defenders with very good average depth of tackles (2.9 and 2.0 respectively) and you would think they are handling outside runs, the problem is our EDGEs aren’t volume run stoppers, recording a tackle on only 8 of 112 run defense snaps. But the Eagles are highest in the league for how many tackles their linebackers, safeties, and corners make at 75 of their 112 run defense snaps.

Part of this is scheme with our corners and safeties so deep, part is regression of Fletch, and part is weaknesses in our back seven. But so far this year our opponents are running outside of our defensive front and winning at it.

The pass defense is being dinked to death

Gannon’s defense is meant to take away explosive plays
Gannon has gotten a lot of criticism this week, some deserved as he has been slow or resistant to change and had some head-scratching personnel decisions, but, like Hurts, he needs to be given more time as the Eagles don’t have the personnel to do what he wants. Gannon’s defense prioritizes limiting explosive plays which is where most defenses are going and it is analytically correct. A single explosive play on a drive triples the chances of a score.

The second chart above in the run defense section shows that the Eagles are successful here so far – they are tied with Arizona for 2nd in the league in fewest explosive passes allowed, behind only Buffalo. This is what we want the defense to be.

But the point of limiting explosive plays is making long drives difficult which the Eagles are not doing
The Eagles are 29th in the league, allowing an average drive length of 8.9 plays, ahead of the Rams, Giants, and Football Team (when can we start calling them the Red Hogs?). Last year the Eagles defense was 7th best in the league in drive length allowed.

The Eagles opponents, whether by design or taking advantage of off-coverage, are living off of short passing. The Eagles force the 3rd lowest average depth of target in the league behind Buffalo and Tamp Bay, but are 29th in the league in EPA per pass play allowed (ahead of only Detroit and Jacksonville).

And the linebackers show up as an issue again
The Eagles linebackers are heavily targeted by opposing quarterbacks, rankings 31st in the league in number of targets and receptions allowed, 2nd most targets in the league.

Gannon caused an uproar on Tuesday when explaining why Eric Wilson was on Tyreek Hill last week he said they aren’t a dime defense “yet”. While most saw this as inflexibility, it may be him choosing Eric Wilson in coverage over Zech or Josiah Scott. Not playing dime makes no sense to me but those aren’t great choices and we have to assume Gannon knows Zech and Josiah’s readiness better than we do. I still think it is a mistake but it isn’t like he was sitting Jaire.

Looking at Gannon’s recent past in Indy, he has used dime but had odd personnel usages alternating between little to no dime to one of the higher in the league (data from FootballOutsiders). Gannon was not coordinator in MIN or IND so not sure how much control he had on the personnel usage though. And in Indy, he also had Darius Leonard:

  • 2020 (IND) – Last in the league, running dime 0% of the time
  • 2019 (IND) – 11th in the league, running dime 20% of the time
  • 2018 (IND) – 9th in the league usage of dime at 20%
  • 2017 (MIN) – 28th in the league at 0%

On the defensive side, Howie has only invested on the line and ignored everything else so Gannon has what he has to work with. Against Kansas City you saw an adjustment with Slay both traveling with Tyreek Hill after halftime and playing much more press (not sure why the game didn’t start this way). As bad as they have been these past few weeks, the Eagles defense is allowing fewer explosive plays and a lower EPA per pass play than last year. My biggest issue so far is there is little adjustment and less disguising looks.

And an updated 2022 mock!

If you have gotten this far, just a quick 3-round 2022 mock with where my current thinking is. These are extremely anti-Howie picks so not saying it is what will happen, it just is what should happen building on the above. For this I am using MockDraftDatabase’s simulator which gives the Eagles picks 4, 6, and 9 in the first. Just speculating, but if Howie has three higher firsts, I think he trades one of them down but for now I will go with what the simulator uses.

  • R1-4 CB Kaiir Elam – I will believe Howie takes a corner high when I see it, but corner remains the Eagles biggest go-forward need as both Slay and Nelson are likely gone by 2023. I don’t care about the Eagles league-leading zone usage – Kaiir leads college football in press snaps and has allowed no completions in press coverage.
  • R1-6 S Kyle Hamilton – Another one Howie would never do but Gannon’s defense needs playmakers and the Eagles only have one actual safety right now in McLeod who is a free agent after this year. Kyle is bonkers good and would be somebody that could be moved all over on defense.
  • R1-9 EDGE Aidan Hutchinson – Finally a Howie pick… I considered an offensive linemen here as that is a need, but Aidan is an amazing disruptor and has been unblockable this year at Michigan. Barnett will be gone this year and replenishing the line is a need.
  • R2-40 LB Devin Lloyd – I really wanted to take a linemen here but thought I couldn’t write a thousand words on why the LBs are awful and not take Lloyd here. The Eagles have a ton of “potentials” at LB and I have hope that Davion can become a solid LB, but even if he does emerge, they need another LB.
  • R3-71 OL Jamaree Salyer – Much later than I wanted an offensive linemen, but Georgia’s current LT can play across the line but is probably a guard in the NFL. He has not allowed a sack in 615 dropbacks across 4 years.

A very defense and secondary heavy draft (if I mocked more rounds, I would have a second corner in there). There are plenty of needs and you can argue the ordering or picks, but investing in the back 7 is what needs to happen. Howie’s philosophy of investing in the DL and de-prioritizing everything behind it is exactly wrong. Good pass coverage has a higher correlation to better defensive EPA allowed than a good pass rush does (analysis from Eric Eager and George Chahrouri here) which is so counter-intuitive to the Eagles way. Sure, a pass rush is great and is needed, but offenses are scheming around quick pressure and, as shown above, forcing short throws isn’t really working for the Eagles so far.