What the change to Steve Spagnuolo and the 4-3 Under means for the Chiefs’ secondary

After the Kansas City Chiefs hired Steve Spagnuolo, our own Craig Stout posted an article explaining the main components in the alignment and personnel of his usual defensive scheme.

Piggybacking off of Craig, I’m going to quickly talk about Spagnuolo’s secondary usage both in terms of personnel, some desired traits and mention some coverage concepts he likes to utilize.

This is in no way attempting to be a full breakdown or provide a ton of depth—it’s more of a primer piece to what will be an extremely fun summer for both Craig Stout and I (as well as many others) as we learn a new defense all the way through.

The secondary

The defensive backs are the forgotten man in this move because, quite simply, any coverage scheme can be run behind a 4-3 Under/Over front.

The Seattle Seahawks have popularized the Cover 3 out of it, college teams like the Michigan Wolverines have run-heavy Zone Blitz concepts as well as heavy man coverage, and Spagnuolo himself has done it all.

Coverage

Man Coverage: The most common coverage for recent Spagnuolo defenses has been based out of Cover 4 but with MOD (man only deep) and MEG (man everywhere he goes) adjustments. It plays out a ton like man coverage.

There is also pure man coverage involved as well. Some music for Chiefs fans’ ears should be the fact that there is rarely very soft off-man coverage from his defenses. There is plenty of press-bail technique, plenty of press-mirror, catch-man and some press-man, but rarely will defenders be seven or more yards off and still pedal off the snap.

There will also be a rotation of both single-high and split-safety looks, changing based on opponent, personnel and game flow.

Zone Coverage: Most commonly a pattern-match variety and often paired with exotic blitz packages, Spagnuolo does mix up his zone coverage often. Some games and matchups will see more zone and some will see less but rarely will the main coverage for an entire game be a static zone like a Cover 3 or Tampa 2 look. There is a heavy influence of Match Quarters in the defense which combines zone and man principles.

Run responsibilities

Outside defensive backs: Outside cornerbacks don’t often have over-the-top help and rarely are playing full face-to-the-ball coverage, so their run responsibilities are minimal and they should only be breaking on the run once the ball crosses the line of scrimmage.

Apex defensive backs (including slot cornerbacks): The strong safeties do have direct run responsibilities, which is why it’s somewhat surprising that on run downs in the nickel package, Spagnuolo still prefers to use three cornerbacks rather than a third safety. A weak-side and/or slot cornerback is just a force player that is either pushing the running back inside to the defenders spilling it outside or stretching the run out completely laterally to the sideline.

The strong safety has different fits based on the front (Over/Under which will be gone into later) but they do have some interior gap responsibilities that ask them to spill and have some force responsibilities.

Personnel

Cornerback: Spagnuolo plays three cornerbacks heavily and almost exclusively three cornerbacks in the nickel.

Depending on personnel, the third cornerback can play inside or outside depending on how Spagnuolo feels. The players have to be comfortable in a variety of techniques but the most important trait is quick feet, quick change of direction skills and the ability to mirror wide receivers. Kendall Fuller is a very good fit with his patient feet and flexibility but does have to improve carrying vertically. Charvarius Ward showed a ton of promise as an outside cornerback but there are some red flags if he’s asked to mirror and play catch man. Tremon Smith is still a project and developing but he’s also a blank slate.

Safety: The most important position in Spagnuolo’s defense is the strong safety, or at least in his most previous stint with the New York Giants. Landon Collins was used as a man defender against tight ends, running backs and occasionally wide receivers. He often was cutting, trapping or in a robber role when playing in zone and was a frequent blitzer off the edge or up the middle.

The free safety most often played deep but would kick down to the weak side in man coverage against wide receivers or running backs, which also means that the strong safety has to be comfortable playing deep, including single-high duties.

If Eric Berry is fully healthy he clearly projects well to that strong safety role with his ability in man, underneath zones, deep zones and the ability to be the vocal leader of the defense but relying on him to be healthy seems like a massive stretch.

Jordan Lucas shows the best ability to be able to play deep zones (single-high specifically) and drop down into man coverage on slot wide receivers.

Winners

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Yeah, Landon Collins is probably wishful thinking at this point, especially with the current cash spending of the Chiefs’ safety room, but Collins was drafted by Spagnuolo and enjoyed his three best seasons with him. Collins currently is an unrestricted free agent and while the Giants can very easily Franchise Tag him, there have been rumblings of uncertainty if he wants to be there and if they want him back (trade rumors, Chiefs being potentially interested). Kendall Fuller is another winner, as he’ll often be asked to play techniques that are a bit more beneficial to his skills and get to play more zone coverage, which he excelled at previously.

Losers

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The Chiefs have a roster of safeties that are capable of a bunch of tasks but don’t particularly excel at any of them. For that reason, Daniel Sorensen and Armani Watts fall into the losers category because of the specific asks of the defense.

A safety has to either be very adept in man against tight ends, as well as a great run defender, OR a rangy deep safety that has man coverage skills good enough for a slot wide receiver. Lucas best fits the mold for the latter on the team and Eric Berry, if healthy, is definitely the best for the former. Sorensen nor Watts have shown the skills to perform either and given Spagnuolo’s lack of third safety usage, there may not be a place for them.

So there’s where the current personnel would fit into a Spagnuolo secondary and a little about his concepts and principles. Do you feel better about the switch? Worse?

Where do you think the Chiefs need to attack to improve it in free agency and in the draft?