FOXBORO — Stephon Gilmore's coverage assignments on a week-to-week basis are typically pretty easy to decipher well before the game is played.
Who's the opposing team's best receiver? That's Gilmore's guy.
The Patriots play about as much man-to-man defense as any team in the league, in part because of their ability to effectively erase one talented option thanks to their No. 1 corner.
But the answer to that question — who does Gilmore have? — is a little more complicated this week. The Eagles have what might be the worst collection of receivers in the NFL. They also happen to have one of the most talented pass-catching tight ends in football in Zach Ertz.
So would the Patriots be willing to stick Gilmore on Ertz? Best corner on best pass-catcher? And would using Gilmore on a receiver, say Alshon Jeffery (if he even plays), qualify as wasting a valuable coverage player?
The Eagles are preparing for the possibility that Gilmore ends up with the atypical assignment of matching up with a tight end this week.
"We know that they are a match-up defense and that they are going to study us and the matchups and how they relate to their defensive backs, and they are going to match-up Stephon with somebody," said Philly offensive coordinator Mike Groh. "Could be Zach. Talked about that. We certainly know that's a possibility. We won't really know until we get out there, but we know that that's their M.O."
It's a possibility. And it wouldn't come as a mind-blowing surprise for Gilmore to see a snap or two on Ertz. But for Gilmore to shadow Ertz would be unprecedented for him as a member of the Patriots.
According to Pro Football Focus, Gilmore has been targeted while responsible for a tight end just eight times since joining the Patriots. Two of those came a few weeks ago against the Giants, when Rhett Ellison ran a route into Gilmore's zone. One came back in Week 4, when the Patriots were in a prevent-style look on a third-and-24 snap and Dawson Knox wandered into Gilmore's area.
Two of Gilmore's tight end targets came against top-tier players in man-to-man coverage: one was on Ertz, in Super Bowl LII, when the Eagles ran three pass-catchers out of a bunch formation and Gilmore had the first player to release outside; the other was on Travis Kelce during last season's AFC title game, when Gilmore aligned over Kelce in the slot and forced a fumble after Kelce made a catch one yard beyond the line of scrimmage (the call was reversed on a Patriots defensive penalty called on J.C. Jackson).
So Gilmore consistently matching up on a tight end is rare. But Eagles receivers are becoming such an afterthought that using Gilmore on Jeffery or Nelson Agholor might be a misappropriation of assets.
Perhaps there will be instances when the Patriots treat Ertz — who checks in at 6-foot-5, 250 pounds — like a receiver. Devin McCourty admitted on Wednesday that differentiating between when Ertz is a tight end and when he's a receiver makes him a tough cover.
"I think they use two-tight end sets more than really any football team," McCourty said. "The two types of tight ends they have, both those guys are 4.7, 4.6 [40-yard dash] guys. They run great routes. They split out wide. Whether you call it '12' with two tight ends, or is it '11' with three receivers, they have that kind of versatility ... I think you just have to know what we want to do as a defense. Like, we could sub in another group. You don’t know. And as much as you kind of want to have that planned out going into the game, sometimes the game dictates what you end up in.
"You don’t know how the game’s going to kind of turn out, so we could practice all week like, 'Hey, we’re going to do this,' and then the game kind of develops and we’re like, 'Oh, we don’t like that, let’s do this.' So, I think it’s understanding who’s in the game, what they’re trying to do, and then what we’re trying to do and then mesh all of that together. I mean, it sounds simple, but within that, knowing what they want to do and what we want to do, that’s the tough part about playing in this league."
One option for the Patriots would be to make sure they're fairly certain how Ertz will be used before they send a defender after him. If they know he's going to be running a route, let Gilmore cover him. Ertz has a snap percentage this season that splits his receiver plays (where he runs a route) and his run-blocking snaps at about 60-40. He's clearly more receiver than he is blocker, but the Patriots could wait for obvious passing situations to let him take Ertz.
Another option would be for the Patriots to do what they did in the AFC title game. It was Jackson who saw Kelce for the majority of that game, while Gilmore took Sammy Watkins. Again, Jeffery now might not pose the same kind of threat that Watkins did then. But having a physical man-to-man corner like Jackson chase Ertz around the field could make sense. Jackson was targeted three times while on Kelce in Kansas City, allowing just one catch (a touchdown) for 12 yards.
The Patriots could also double Ertz with a combination of players coming from different positions. The Lions, led by former Patriots defensive coordinator Matt Patricia, doubled Ertz on third down and in the red zone — something the Patriots have done historically against an opponent's top receiver — and often did so with a defensive back and a linebacker helping out. The same could happen if the Patriots wanted to treat Ertz as a big slot receiver, bracketing him off the line of scrimmage.
Letting Gilmore shadow Ertz all over the field could be the easiest answer, even if it leaves Gilmore somewhat vulnerable against the run since he'll be an easy target for a player 50 pounds heavier.
Gilmore has taken big receivers before, including Kelvin Benjamin, who's listed at 6-foot-5, 245-pounds, and siccing him on Ertz might be the simplest way to handle the Eagles passing game. Complicating the coverage plan for Philly's best pass-catcher might be difficult if the Eagles use an up-tempo attack or ask Ertz to align all over the field from one snap to the next; the communication alone might be hard to get straightened out in just a few seconds if that's the case.
But if the Patriots opt to stick their top corner on a tight end, it'll be the first time they've done so with Gilmore. It's one of the reasons this matchup is one of the most fascinating the Patriots have faced this season.
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