Chiefs defensive trends and tabulation for Week 15

On Sunday, the Kansas City Chiefs defense lined up against a run-heavy Denver Broncos offense with a big-armed young quarterback and a dangerous vertical target.

And even in the inclement weather conditions, the Chiefs defense was dominant for yet another week.

Drew Lock, Phillip Lindsay and Courtland Sutton weren’t able to punch the ball into the end zone all day as the Chiefs cruised to a comfortable victory — one in which the defense gave up only a single field goal.

As we do each week, we’ll take a look at the numbers to see where the Chiefs found success and failure. Then we’ll then take a look at something good, something bad and something you may have missed in the Broncos game.

The numbers

The Chiefs defense was dominant in almost every facet of the game against the Broncos. They allowed 4.4 yards per play, didn’t have a single quarter with a defensive success rate below 57% and held the Broncos to a third-down conversion rate of just 36%.

The Broncos went 0-for-2 inside the red zone, boosting the Chiefs defense to sixth in red-zone defense. Its performance also raised them to a tie for 10th in scoring defense.

After some rough patches, the Chiefs defense has really found its groove.

Steve Spagnuolo ran an awful lot of dime defense against the Broncos. Spagnuolo opted to treat tight end Noah Fant as a receiver, choosing to defend Denver’s 12 personnel like it was 11 personnel. This left lighter boxes, daring the Broncos to run late in the game when they still needed three touchdowns to make a comeback.

Spagnuolo brought the heat against the Broncos’ rookie quarterback and shaky offensive line. He brought pressure from every level of the defense and got advantageous matchups, getting Alex Okafor and Frank Clark free runs at the quarterback by firing blitzers at interior gaps. Spagnuolo even put some three-man rushes on tape, dropping both defensive ends into coverage and blitzing a with a linebacker. He definitely kept the Broncos offensive line on their toes.

Since Spagnuolo ratcheted up some big blitzes against the Broncos, it only makes sense that he’d attempt to play man coverage on the back end. The Chiefs really mixed things up with some new-to-them looks in zone, too. We’ll come back to that.

Something good

Spagnuolo deserves the lion’s share of the credit, turning an awful defense into a good one of a single year — particularly in the secondary. But Tyrann Mathieu’s involvement in the turnaround has been enormous.

For several weeks now, Mathieu has been playing like a man possessed. But his play throughout the year has mostly been top-notch. He’s been asked to play in the box and as a deep safety — and has also been the primary slot defender ever since Kendall Fuller first went out with his hand injury. He’s played in pretty much every position he could feasibly play in the secondary — and at a high level.

We got to see that in spades on Sunday. His biggest highlight came on a corner route to Sutton for a sure touchdown — one that Mathieu stole from him by ripping the ball away from the much bigger receiver.

Mathieu has also been an extension of Spagnuolo on the field, adjusting the secondary and making sure everybody is on the right page. In that regard, he has been exceptional.

It’s a motley crew in the secondary. Mathieu is playing with a rookie safety (albeit one who is playing quite well) two cornerbacks picked up off the street on one-year deals and an undrafted free agent from 2018 who was acquired for a player the Chiefs were probably going to cut. But they are playing well; the whole is considerably above the sum of the parts.

That’s due in no small part to their efforts in the film room and their ability to seamlessly communicate on the field — which Mathieu has facilitated. At this time last year, Eric Berry finally set foot on the field and had to show the secondary exactly where to line up in Bob Sutton’s simpler defensive scheme. This year, the secondary is throwing the kitchen sink at opposing offenses with minimal miscommunication errors.

Finally, the defense has decidedly adopted Mathieu’s approach and mentality on the field. Early in the year, the defense was tentative; they were still feeling out what Spagnuolo expected of them. But over the past four games, the defense is carrying itself much differently. Its hallmarks are aggression, intensity and swagger — and a large part of that stems from Mathieu ‘s influence.

For the Honey Badger, Sunday was a highlight factory. But his fingerprints are all over the Chiefs defense.

Something bad

For the second week in a row, there wasn’t much to complain about on defense. However, the Chiefs did give up a single explosive play — this 43-yard pass to Fant on fourth-and-1.

Understandably, Charvarius Ward is peeking into the backfield during the play-action in a short-yardage situation. Fant does well to sell the block before releasing upfield behind a late-reacting Ward. The tight end definitely has some speed, so he’s able to gain separation on the reception.

Ward was able to chase him down and blow up the play, but had he been able to identify it slightly faster, the Chiefs defense might have pushed the Broncos off the field.

Something you may have missed

I mentioned that Spagnuolo threw out some different zone looks on Sunday. Here are two examples of what he used against the Broncos’ rookie quarterback.

I’ve talked about how Spagnuolo will drop the slot cornerback into a deep zone, calling it a slot-drop Cover 2. Typically, the slot cornerback has dropped straight back — with the deep safety rotating to the opposite field over the top. But late in the Sunday’s game, Spagnuolo had the slot corner bail to the opposite deep zone.

Fuller takes off early — knowing that he’s got a lot of ground to cover — and crosses over to the field zone to help over the top. It’s a small wrinkle, but one that opposing quarterbacks will have to note in the weeks to come. Waiting to see whether or not Fuller is dropping straight back or across the field may result in an extra split second for the pass rush to get home.

This is a more exotic look: an inverted Cover 3 coverage shell. Gregg Williams used to lean on a similar coverage call in third and long situations during his time with the Rams, dropping the nickel corner to the deep third of the field.

Spagnuolo puts his own stamp on the coverage, dropping Daniel Sorensen deep from a dime linebacker role; Juan Thornhill even takes an early step to try to sell a Tampa 2 look to the quarterback.

On the snap, the two deep safeties do not gain depth and sit in the high hole at the first down marker — the typical spot to try to attack a Tampa 2 coverage. The cornerbacks carry vertically and zone off to a deep third. At first, Lock looks to hit the high hole, but identifies the safeties and checks it down on third-and-12. The underneath defenders rally to the ball and get off the field.

Against the Brocnos, Spagnuolo wasn’t just trying to confuse their rookie quarterback. He was also putting extra coverage looks on tape for the remainder of the season — and the playoffs. As the season has progressed, we’ve seen more and more wrinkles to the coverage scheme. Those extra layers have caught some quarterbacks off-guard — notably Tom Brady in Week 14 — and will only make the defense more formidable the rest of the way.

The bottom line

This Chiefs defense is brimming with confidence and playing at a very high level, making bad offenses look worse. Instead of the bend-but-don’t-break mentality we grew accustomed to seeing, the unit is coming up with regular stops. They’re winning at every level — and stepping up when the team needs them most.

This unit is coming together, playing some of its best football at just the right time. With Frank Clark getting healthier — and the addition of Terrell Suggs — there’s reason to believe that it’s going to keep getting better.

A mere month and a half ago, there we were talking about how a Patrick Mahomes-led offense hadn’t ever received enough help from the defense. But now it’s safe to say that the defense is more than holding up its end of the deal.

And they’re still not satisfied.