A season after the Lions defense gave Bill Belichick a blueprint for slowing down the Rams offense in Super Bowl 53, the favor was returned when Matt Patricia drew inspiration from his mentor in order to attempt the impossible: Slow down a Chiefs offense that hadn’t scored fewer than 26 points since Patrick Mahomes took over as the team’s starting quarterback last season.

Detroit put together a good plan. And, despite coming into the game banged up — star corner Darius Slay and defensive tackles Mike Daniels and Da’Shawn Hand missed the game — the Lions executed Patricia’s Belichick-inspired plan as well as anyone could have hoped. There were a few mix-ups in coverage and some plays where an undisciplined rush allowed Mahomes to scramble for chunks of yardage; but, overall, the Lions defense DID ITS JOB™.

And guess what? It didn’t matter. The Chiefs offense still put up 27 points (with another touchdown being scored by the defense) and would have scored even more if not for the offense catching a case of fumble-itis. Mahomes averaged 0.27 Expected Points Added per dropback. And he did it without his best wide receiver, Tyreek Hill, on the field.

The Lions came up with a near-perfect plan and executed it nearly perfectly. It didn’t matter. Because Patrick Mahomes is an alien and the best quarterback in the NFL. What sets Mahomes apart right now is that he as both the physical tools and football IQ to deal with everything thrown his way — and the Lions threw A LOT his way.

I guess you can call what Belichick and Patricia did to “frustrate” the Chiefs offense a “blueprint” that other defenses can attempt to follow, but this one is not nearly as effective as their blueprint for stopping the Rams, which has been successfully utilized by defenses across the league. And that has everything to do the Chiefs’ and Rams’ respective quarterbacks. While Jared Goff has struggled to figure out a Plan B, Mahomes has had no trouble succeeding with Plans B, C and sometimes even D. That’s why the Rams offense has sputtered early on in 2019 while the Chiefs machine continues to churn out points.

So what exactly did the Lions do to give the Chiefs problems, and how did Mahomes’ brilliance render all of that good planning useless? Let’s take a look…

First, a brief summary of Detroit’s defensive gameplan: The Lions played a ton of man coverage. To deal with the Chiefs’ speed — which is more important when you’re asking defenders to run step-for-step with receivers all game — Patricia always made sure to play more defensive backs than the Chiefs had receivers on the field. So against 11 personnel sets (1 RB, 1 TE, 3 WRs), Detroit matched with a dime package (6 DBs). When another tight end joined Travis Kelce on the field, the Lions matched with nickel (5 DBs). Kansas City might be the fastest team in the league, and Detroit wasn’t going to get burned.

In order to deal with Kansas City’s RPO game, Patricia had to ask a lot of his defensive front. There was no getting an extra man in the box to stop the run. Certain defenders, like Trey Flowers (an end who played a lot of tackle in this game) and Damon Harrison would have to be responsible for two run gaps in order to take run-pass conflict off of the second-level defenders.

The Chiefs ripped off some big runs as a result…

But Patricia adjusted well…

He eventually settled on a front that conceded the A-gaps in order to better defend the B-gaps, which is where Spread/RPO teams really like to attack.

I don’t know if Patricia was just desperate or actually had confidence in his linebackers to fill those A-gaps, but, whatever the case, they were up to the task.

Despite enjoying a numbers advantage in the box on almost every snap, the Chiefs run game was largely ineffective. Kansas City’s 20 designed run plays averaged -0.04 EPA.

With the run game stymied and Detroit’s pass rush not giving Mahomes all day to throw, as the Ravens did, this game ultimately came down to coverage. I don’t know if it matters what kind of coverage you play against the Chiefs, but it’s become pretty apparent over the last year-plus that if you try to play zone defense against this offense, you don’t stand a chance. In 2018, no quarterback was better than Mahomes against zone coverages.

Patricia realized this and planned accordingly. The Lions play a lot of man coverage to begin with, but they increased their usage in Week 4, playing some variation of man-to-man on 36 of Mahomes’ 48 dropbacks. So, for the most part, this gameplan was all about matchups, and Patricia did a good job of putting his defensive backs against players they could handle.

Sammy Watkins drew Justin Coleman, DeMarcus Robinson got Rashaan Melvin. Mike Ford, stepping in for the injured Slay, had to run with Mecole Hardman and his 4.33 speed. And that left safety Tracy Walker on Travis Kelce.

For the most part, all those guys did a fine job carrying out their assignments. Coleman was arguably the best defensive player on the field on Sunday. He made a number of difficult plays, including this crazy pass breakup on what looked like a sure touchdown…

Even with the Lions sticking tight to Chiefs receivers, Mahomes found a way. Whether it was firing laser beams into tight windows…

Or throwing across his body after escaping the pocket…

Mahomes was forced to make difficult throws all afternoon. His Expected Completion Percentage, a metric developed by the NFL’s Next Gen Stats, was 55.8% for the game. It had been hovering around the mid-60s for the first three weeks of the season. The Lions secondary had won its matchup against the Chiefs receivers … and it didn’t stop Mahomes from moving his offense up and down the field.

The big issue with playing man coverage against a mobile quarterback is keeping him in the pocket. Because the coverage players have their back to the pocket and can’t see when the quarterback takes off.

Early on, the Lions made sure to have a defender (sometimes multiple defenders) lurking in the middle of the field with eyes on Mahomes. Here, Jarrad Davis (40) has the responsibility…

That required Detroit to play with only one safety deep, which can create more problems with all of the speed the Chiefs have on the perimeter. And after safety Quandre Diggs, who had been patrolling the deep middle, left the game with an injury, it became downright impossible to continue to play those single-high coverages.

So the Lions played more two-deep coverages down the stretch, taking Walker off of Kelce and asking him to play deep alongside Diggs’ replacement. That, in turn, took those extra eyes off the pocket and we saw why that was a problem on the play that eventually led to Detroit’s demise: Mahomes’ scramble on 4th-and-eight late in the final quarter…

Detroit has every route covered, which Mahomes quickly realizes. And with the Lions rushing only three — something they did often in order to commit numbers to cover the Chiefs talented receivers — he had plenty of space to take off for the game-extending run.

The pocket wasn’t always so clean for Mahomes. Patricia did a good job of sending rushers from all angles and always changing the pre-snap picture for the Chiefs offensive line. Like the Patriots before them, the Lions did a tremendous job of forcing Mahomes to move off his spot in the pocket, and did so without committing extra numbers to the rush. But that’s where Mahomes has grown most as a quarterback in 2019: He’s so much better at dealing with pressure and finding options downfield.

Here’s a “creeper” pressure (a four-man rush that includes a traditional rusher dropping into coverage and a second- or third-level defender replacing him in the rush) from Detroit that gives the Chiefs offensive line some issues.

Last season, Mahomes may have pulled the ball down or forced a throw to his first read. In 2019, he remains calm, finds Kelce, who wasn’t his first option on the play, and throws a perfectly-placed pass to move the chains. This happened on more than one occasion.

It’s unfair. Playing this Chiefs offense is like playing a twisted game of whack-of-mole: No matter how many moles you think you’ve whacked, there are several others ready to pop up. Even when a coach out-schemes Andy Reid (which Patricia did) AND gets all of the Chiefs receivers covered (which the Lions secondary did) AND figures out how to stop the run (which Detroit’s defensive front did), you still have Mahomes extending the play and throwing strikes downfield or taking off for game-changing runs.

Patricia pitched a perfect game on Sunday and STILL lost. That just goes to show even the perfect plan is no match for the NFL’s best quarterback. And there is no debating who owns that title at the moment.