The one thing the Patriots defense can do that will send New England to Super Bowl 53

You know all about the Chiefs.

You know about their offense and its place atop the lists of every major team metric — total offense, DVOA, expected points, etc. You know all about phenom Patrick Mahomes and his 50-touchdown, 5,000-yard season, replete with a unique repertoire of no-look passes and side-armed seeds.

You know about the MVP-favorite’s supporting cast of elite weapons like Tyreek Hill, Travis Kelce, and Sammy Watkins. You know about the star-studded offensive line in front of him. And you know all about the cunning, imaginative scheme with which Andy Reid deploys this potent stable of personnel.

What you may not know is, the Patriots defense has already unlocked the formula for slowing Kansas City’s ceaseless attack — and it comes down to one almost-too-simple-to-believe concept that, if executed, will send the Patriots to their ninth Super Bowl in 18 years.

Put a pin in that for a moment. First, after charting each and every play from the Patriots and Chiefs’ week-six match up, there were a few specific approaches New England’s defense took which led to short stints of success.

(1). The Patriots threw out their traditional base defense altogether. Although Malcom Brown being sidelined with an injury from the prior week led to increased snaps and less rest for the three active interior defensive lineman — Lawrence Guy, Danny Shelton, and Adam Butler — it became clear from the onset that the Patriots were never going to match any of Kansas City’s heavy personnel groupings with four-DL looks anyways. Instead, the Patriots opted for mobility up front, using three linebackers on just 45.3% of plays, and never using a personnel grouping heavier than 3-3-5 Big Nickel the entire game — even on the goal line.

(2.) The defense held up against Kansas City’s vaunted RPOs pretty well. The Chiefs used them 13 times — nine running plays and four passing plays. However, sound assignment integrity and tackling work by the Patriots’ linebackers and secondary held these typically lethal plays to a total of 86 yards (6.6 yards per play), and just two first downs.

(3.) Brian Flores dialed up well-timed, key blitzes. The Patriots brought more than four rushers on eight different occasions in the contest and consistently changed where the additional rushers came from:

• Elandon Roberts | “green dog”, A-gap
• Kyle Van Noy | left B-gap
• Duron Harmon | right B-gap
• Dont’a Hightower | left edge
• Dont’a Hightower & Kyle Van Noy | right edge & left A-gap
• Dont’a Hightower | right edge
• Dont’a Hightower | right edge
• Patrick Chung | left slot

Patrick Mahomes went four for eight against these blitzes for 26 yards and one touchdown, which came from the New England one yard line in the fourth quarter. In total, the Patriots forced three field goal tries in their own territory with these blitzes.

(4). The Patriots constantly showed Mahomes pre-snap blitz looks throughout the game, and would often have each “blitzer” engage blockers post-snap, only to have a few — or all — of them fall back underneath into coverage. Not only did this have the desired effect of disguising where the pressure would be coming from, but it helped to obfuscate potential lanes of escape from the pocket for Mahomes. This concept led directly to Dont’a Hightower’s first quarter interception.

All of these approaches helped to stall drives and slow down the league’s most dynamic attack. However, there was one effective aspect of New England’s defensive game plan that gave Kansas City’s offense more issues than any other — the one almost-too-simple-to-believe component that, if harnessed and fully-utilized on Sunday in Kansas City, will send the Patriots to Atlanta.

Man coverage.

Seriously. Man coverage. It’s that simple.

The Patriots defensive scheme is often referred to as a “press-man heavy”, but in actuality, they’ve used man coverage on around 57% of passing plays in 2018. In week six against the Chiefs they used it 56.76% of the time — and when they didn’t, they paid the price.

Yes, that’s real. Of Patrick Mahomes’ 352 passing yards in week six, 279 came against zone coverage, including Kareem Hunt’s 67-yard third quarter touchdown, and Tyreek Hill’s 75-yard game-tying touchdown in the fourth quarter. Seven of the 13 completions against the Patriots’ zone coverage went for first downs, and all seven went for over 17 yards.

Against Man coverage, the Patriots allowed five first downs on five more pass attempts, but Mahomes failed to complete a pass over 15 yards, and both of New England’s interceptions came against their man scheme.

The disparity also extends to the Chiefs usage of play action (not to be confused with RPO). Mahomes and company used play action six times — twice against man, and four times against zone. Against man, the Patriots had an interception and allowed a 15-yard completion. Against zone, Mahomes went three for four and notched 119 yards and a touchdown.

So why was man coverage so effective against the Chiefs while zone coverage was not? The biggest factor was YAC — yards after the catch. Against zone, Kansas City averaged 10.31 air yards per catch, but after the catch, they racked up 168 yards. That’s an additional 12.92 yards tacked onto each reception. Against man coverage, the Chiefs we’re held to just 28 yards after the catch (2.8 avg. YAC).

The second major factor is the nature of zone coverage itself. It allows free releases off of the line of scrimmage which can allow the offense’s timing to remain on schedule through the initial stage of the play design. It can lead to disadvantageous personnel match ups for the defense. Creases naturally occur on the backside of RPOs. And, often times, there is no defender trailing the intended passing target in coverage.

Andy Reid’s scheme is the kryptonite for each of these shortcomings — particularly with regard to taking advantage of a zone’s reactionary flow resulting from an RPO or biting on a play action fake. And he uses formation, motion, spacing, and angles perfectly to get his skill position players in position to inflict the most damage.

In week six, Patrick Mahomes consistently threw well-placed footballs to allow his guys to slice through seams of the Patriots zones (see: Tyreek Hill’s 75-yard touchdown). And, as the second-year stud kept initially well-defended plays alive by escaping the pocket, the integrity of those zones became stressed and began to break down, leading to big plays.

Are there risks to playing man coverage against the kind of weapons that the Chiefs have? Sure. But by playing man-to-man, you limit yards after the catch, you decrease the size of the windows Mahomes has to throw into, and you force their play-makers to continuously make more difficult plays.

Perhaps more importantly, it would force a young quarterback venturing into the high-pressure environment of an AFC Championship Game for the first time to play near-perfect football — a tall order.

Follow Brian Phillips on Twitter — @BPhillips_SB