How much will change for the Eagles if Darius Slay shadows WR1s?

Sometimes, coach-speak is just coach-speak. Football guys want to get in and out of podium sessions as quickly as they can, and with tired idioms ever permissible by sportswriters just looking for a soundbyte, they can say enough while really saying nothing. Eagles DC Jim Schwartz has long been an expert in this field.

But last week during media availability, he gave a long and detailed answer to a question on newly-acquired CB Darius Slay, and how he’ll be used in the Eagles’ defense. The full answer can be read here.

The simple reality is that Slay is the best corner that Schwartz has had in Philly, and it’s going to allow him to do different things than he’s ever done before. During his career with the Eagles, Schwartz has leaned to zone coverage over man coverage relative to some of his initial schemes in Detroit and Buffalo. Last season, Philly was in zone coverage for 58% of their defensive snaps, which is around league average — but unlike many systems that spin into different coverage shells or play zone behind second-level blitzers, the Eagles keep things relatively simple.

Jim Schwartz only likes to keep only one safety deep to add the other safety into the box, beefing up his numbers against the run and freeing his defensive line to play aggressively upfield. As such, the Eagles base their defense in Cover 3 shells, occasionally spinning to Cover 4 looks that still keep the safeties incorporated in the run fit. When they go man coverage, they’ll do it with that single-high safety in Cover 1.

It isn’t great to be predictable in your defensive shells, and it’s even worse if you’re predictable with shaky personnel. Such was the case with Philadelphia and their defensive backs over the last few seasons. Despite the stellar play of Malcolm Jenkins as the box safety and the occasional flashes of quality nickel play in Avonte Maddox and Patrick Robinson, Ronald Darby and Jalen Mills have largely been disappointments at outside cornerback, and deep safety Rodney McLeod didn’t have the necessary range to account for their difficulties. The Eagles bled targets to outside receivers last year accordingly.

When scheme and personnel are both part of the problem, there can be an unintentional paralysis in addressing the issue. As a long-time believer in Rasul Douglas, I think the Eagles would get better coverage out of their outside cornerback spot if they played Rasul in the right way, by letting him press at the line of scrimmage and deny vertical route stems to hide his lack of long speed. But the other argument easily holds: Douglas would play better in Schwartz’s cushioned Cover 3 alignments if he was just better, both physically (faster) and technically (willing to protect himself against deep stems).

So instead of going one way with it, the Eagles seem to be going both ways — and that’s a good call. They’ve improved their personnel in outside corner by trading for star Detroit CB Darius Slay, one of the most productive cover men of the last five years. And they also seem willing to adjust the scheme to fit his toolset, as Schwartz admitted last week that the Eagles will look into allowing Darius Slay to shadow the opponent’s top receiver.

“I don’t know that it’s going to be a 100 percent, all-the-time thing. Maybe it’s a particular game. Maybe it’s 50 percent of the games. Maybe it’s 75 percent of the games that Slay is matching a particular receiver, but you will see that from our defense.”

This is a big shift. In the last three seasons, the Eagles have never once had a corner mirror a receiver for more than five games of the year — in those same three seasons, Slay has mirrored receivers in 10 (2017), 10 (2018) and 9 (2019) games. Here is the production he allowed in 2019 when in shadow responsibility.

Slay was able to shadow the opponent’s top receiver in Detroit because of how willing Detroit was to play man coverage across the board. After extending Slay and shelling out big money for nickel cover man Justin Coleman, the Lions played man coverage at the second-highest rate of any NFL team last season, and in concert with Slay’s shadowing, also had Rashaan Melvin and Justin Coleman frequently in coverage responsibility over just one receiver for the majority of the opponent’s passing attempts.

Predictably, Slay took snaps at a variety of alignments. He was distributed fairly evenly between left outside corner (30y snaps) and right outside corner (371 attempts), with reps in the slot (140) still significant across the course of a season.

This is nothing like how the Eagles deployed their cornerbacks last season. Mills took 10 times the number of snaps at outside corner (388) than he did in the slot (32); Darby’s disparity between outside (461) and slot (8!) was even more drastic. Once Mills was healthy in Week 7, he was the permanent left corner; Darby was the permanent right corner. Their primary slot corner, Avonte Maddox, had more flexibility, with 399 snaps in the slot and 83 out wide — but the lines were still clearly drawn.

If the Eagles are going to let Darius Slay shadow a WR1 for even one game, their current defensive structure and snap distribution is going to have to change. They need to play more man coverage, and their corners must be comfortable playing both man and zone from a wider variety of alignments. This is something Schwartz himself acknowledged in the quote he gave on Slay traveling.

“...[W]hen you acquire a player like Slay, who has that skill set, and can match a receiver, it adds a different layer to it. So now, guys who play nickel are going to need to be able to play outside corner also, because every time Slay lines up at the nickel position, it’s just too easy a tell if the only time he’s in there is man-to-man.”

Understanding the Eagles’ other moves at defensive back this year in light of this comment can provide some clarity on the decisions they’ve made, and the future decisions still waiting for them.

Schwartz described the Eagles’ decision to go to zone looks as a response to teams running pick routes against the Eagles’ man coverage during their Super Bowl run. Part of their solution was using their safeties with corner experience (Malcolm Jenkins, Rodney McLeod) as cover men who could handle switch releases at the line of scrimmage, letting their outside corners take the slot receiver on those aforementioned pick routes. With the departure of Malcolm Jenkins, perhaps Schwartz feels less comfortable with the defense’s ability to communicate through bunch sets and rub routes. As I noted in my piece on Jalen Mills’ transition to the Jenkins role, he’s struggled in the past to parse those formations and route combinations.

What Mills can offer them in a slot corner role is the ability to transition to an outside corner role/responsibility without confusion or failed responsibility — it’s the position he used to play. So, if the receiver Slay is mirroring moves into the slot, Mills can kick from the slot to outside and still reasonably fill his responsibilities. The same could perhaps be said of Maddox, who is in the running to win the starting outside corner job opposite Slay despite his size. In his rookie 2018 season, Maddox served as a skeleton key for an injury-riddled defense, taking over 100 snaps at slot corner, outside corner, and free safety over the course of the year.

Despite Jenkins’ departure, the Eagles did not prioritize replacing that box safety role, as Mills, free agent acquisition Will Parks, and draft pick K’Von Wallace are all smaller players with more slot corner projections than linebacker-like builds, which is what Jenkins had for the Eagles over the last few seasons. If they don’t feel like they need that role filled anymore, they may be moving to more man coverage shells altogether, in which they need hybrid players who can flex over the No. 2 or 3 receiver and occasionally drop into deep half zones, instead of stacking behind the defensive line in the box.

This would also track with the inevitable increase in man coverage that Slay will force. If the Eagles intend on mirroring with Slay for more than just a game or a series here and there, they will play more man coverage in 2020 than they did in 2019. In general, in order to mirror receivers, you have to largely play man coverage across the board. This construction of Slay mirroring WR1s with a stable of cover men that can go inside, outside (Mills/Maddox), and deep (Wallace/Parks) will allow them to still play some zone, but also cover three and four receiver sets without tipping their hand. It tries to solve both the 2017 problem of tipping man coverage and falling susceptible to pick routes, and the 2019 problem of being extremely bad at covering good receivers.

If the Eagles really do plan for a dramatic paradigm shift in their coverage shells, and are not just providing lip service that they will allow Slay to do something he’s done at a very high level for multiple years, then Slay may mirror for yet another 10 games. Here is a list of the WR1s the Eagles will see over a 16-game season in 2020.

• Week 1 - Terry McLaurin, Washington Football Team
• Week 2 - Robert Woods, Los Angeles Rams
• Week 3 - Tyler Boyd, Cincinnati Bengals
• Week 4 - Deebo Samuel, San Francisco 49ers
• Week 5 - JuJu Smith-Schuster, Pittsburgh Steelers
• Week 6 - Marquise Brown, Baltimore Ravens
• Week 7 - Golden Tate, New York Giants
• Week 8 - Amari Cooper, Dallas Cowboys
• Week 9 - BYE
• Week 10 - Golden Tate, New York Giants
• Week 11 - Odell Beckham Jr., Cleveland Browns
• Week 12 - Tyler Lockett, Seattle Seahawks
• Week 13 - Davante Adams, Green Bay Packers
• Week 14 - Michael Thomas, New Orleans Saints
• Week 15 - DeAndre Hopkins, Arizona Cardinals
• Week 16 - Amari Cooper, Dallas Cowboys
• Week 17 - Terry McLaurin, Washington Football Team

We already know off of Slay’s 2019 shadow responsibilities. that he may follow McLaurin, Cooper, and Adams — that’s already five there. With Beckham, Lockette, Hopkins, and Thomas all also on the schedule, it’s tough to imagine the Eagles denying Slay the opportunity to shadow those Top-10 receivers, if shadowing is indeed on the table.

With Darius Slay added, Malcolm Jenkins gone, and a no-good, very-bad pass defense in the review mirror, we can reasonably expect a couple of things from the Eagles in 2019: more man coverage, and with it, the opportunity to let Darius Slay shadow top receivers. If it works, expect more split-field safety looks and blitzes to boot, as a defense in desperate need of innovation leans into the positive momentum they’ve been looking for in the last two seasons of stagnant play.

But to what degree these changes are made does depend on the designer of that stagnant defense, Jim Schwartz. Slay is the biggest addition made to the Eagles secondary since Jenkins, and perhaps the best player added to the defense under Schwartz’s tenure, now going on five seasons. If any player can force a significant shift, it will be one of his caliber — and it seems it’s legitimately on the table. Now, we have to wait and see.