Steelers Playbook: The Cover-4 scheme, and why Pittsburgh will lean heavily on it in 2025

I haven’t knocked out a Steelers Playbook article in a while, but after visiting training camp last week and studying the Steelers’ defense, it’s time to dive in again. Today’s feature is on a coverage I saw plenty of in Latrobe: Cover-4.

PHILOSOPHY

Cover-4 uses four defensive backs as deep defenders and three additional defenders underneath. It’s a zone coverage, but it incorporates man principles by having defenders match the routes of receivers. It’s a great coverage against 11-personnel teams that want to stretch the field vertically, and it provides the benefit of deploying safeties as extra run-fitters, too.

With the safeties aligning at about ten yards depth, the goal of the coverage is to position them deep enough to defend vertical routes while still being close enough to the line of scrimmage to figure into the run fit. The safeties in cover-4 are alley run-fitters, meaning they are responsible for any play that bounces outside the tackle box. The inclusion of those safeties in the run fit allows edge setters to crash down hard on inside runs and “spill” them to the alley, where the (usually) unblocked safeties can run them down.

Because of the versatility required to execute this scheme, the safeties — or potentially the nickel player if a team is in a sub-package with five defensive backs — are the key to making Cover-4 effective. They must be able to read and react, handle receivers one-on-one in coverage, and close quickly to make solid tackles against the run. If the safeties can do these things, Cover-4 can be very effective at capping deep routes while getting extra hats into the box against the run.

THE SCHEME

In Cover-4, the corners have almost no run responsibility. They are contain players if a run gets to the sideline, but with the way the safeties are deployed, those runs rarely reach the edge.

The corners are integral in pass defense, however. Their basic responsibility is as follows:

If #1 (the widest receiver in the formation) goes vertical further than ten yards, the corner will match him in coverage. At that point, it becomes man-to-man. Some coaches will use eight yards as the decision point. Either way, a deep route from #1, whether it stays vertical, breaks to the post, or bends to the pylon, is the corner’s responsibility.

If #1 goes short or inside, whether on a hitch, slant, quick out, drag route, etc, the corner’s job is to release him and get his eyes on #2. This is usually a slot receiver or tight end. The corner will now help on any deep route from that inside receiver. So, in summary, he is matching #1 vertical, or releasing #1 on any short route and helping on #2.

Against the pass, a safety’s responsibilities are the same as the corner’s, except they read the receivers from inside-out instead of outside-in. If #2 goes vertical, the safety will match him in man coverage. If #2 goes short or to the flat, he will help on #1. Protecting the post is important here, as corners can be vulnerable to in-breaking deep routes.

The three underneath players have inside-gap run support. In coverage, the two widest players must disrupt vertical routes from #2 to help the safeties, and will then sink and work the curl-flat zone. The middle player, who is normally a linebacker but could also be a safety dropping down into a “robber” role, is responsible for crossers and vertical routes in the middle of the field.

Because there are only three underneath players, re-routing receivers by getting hands on them is important to disrupt the timing routes often used to attack Cover-4.

USE IN PITTSBURGH IN 2025

In trading Minkah Fitzpatrick to the Miami Dolphins, the Steelers gave up one of the best deep safeties in the NFL. Fitzpatrick allowed Pittsburgh to play a lot of cover-3, with the corners taking deep outside-third responsibility and Fitzpatrick handling the deep middle, which protected them from explosive plays.

Cover-3 is vulnerable to the popular four verticals concept, however. A good quarterback will look the safety off and throw up the opposite hash. Fitzpatrick’s absence could deter Pittsburgh from playing much Cover-3 for this reason. The additions of corners Darius Slay and Jalen Ramsey, though, gives them better man-match corners than they’ve had in years. Slay played a ton of Cover-4 in Vic Fangio’s scheme in Philadelphia last season, and Ramsey is as versatile a veteran as you’ll find in the league with the ability to play almost any scheme. DeShon Elliott, Pittsburgh’s strong safety, will probably rotate into the underneath zone in Cover-4, allowing him to be a curl/flat defender, while Ramsey takes on vertical responsibilities from the slot. Juan Thornhill, the free agent acquisition from Cleveland who replaces Fitzpatrick at free safety, is athletic enough to carry #2 receivers, and is a dependable tackler who should be solid against the run.

The benefit of having the safeties more involved in the run game cannot be overlooked here. It’s no secret the Steelers were gashed down the stretch last season, and have gone to great lengths to prevent a repeat of that in 2025. Heavier doses of Cover-4 could be part of their run-stopping equation.

In short, the personnel Pittsburgh has assembled in its secondary, coupled with their ability to man-match and their focus on stopping the run, suggest we should see a lot of Cover-4 this season. I saw plenty of it on my visit to training camp, and the team’s beat writers have reported on its continued use since then. Add this coverage to your football vernacular, and look for it when the team kicks off its season in just about a month.

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