Defenses have blunted superstar quarterbacks this season. What happened?

After two decades of booming production, quarterbacks across the NFL have hit a wall this season.

Patrick Mahomes, Aaron Rodgers, Josh Allen and Lamar Jackson, as you would expect, have been great at times this season. But they’ve also suffered down spells, fighting against iffy schemes, rough offensive line play, injuries or illness.

Sometimes the eye test can be wonky though. However, the statistical case is unimpeachable.

Let’s use Expected Points Added (EPA) as a measuring stick. EPA measures the value of each play, assigning a positive or negative score to the offense, defense, and individual player for how they perform above or below what was expected based on the historical precedent.

The current leader among quarterbacks in EPA per play is Kyler Murray. The Cardinals star is the only quarterback in the NFL this season to rank above the 0.250 threshold that marks great play at the position – his current EPA per play sits at 0.263.

Yet that figure would have been unremarkable over the past five seasons. Murray’s current mark would have seen him finish sixth among eligible quarterbacks a year ago, with seven quarterbacks clearing the 0.250 threshold. The year before that, four quarterbacks cleared the mark. The year before that: four again.

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Murray, it should be noted, has missed three games this season. He may well have stretched his lead, but he could also have fallen back towards the pack.

The deeper you dig, the more telling the decline. The league’s middle-class has regressed: The sixth highest-ranked passer this season would have been 16th a season ago. And since Week 9, by which point a whole bunch of teams had hit their all-important bye week and been given the opportunity to tweak their offense, the most effective quarterback in football has been … Taylor Heinicke. And by some distance:

Since Week 9, Taylor Heinicke is first in the EPA+CPOE composite by a pretty ridonculous distance.

*The composite sounds nerdy and complicated. It's not. It measures the value of a play and tries to show how much credit a quarterback deserves for that above the norm* pic.twitter.com/LG4AapVNLz

— Ollie Connolly (@OllieConnolly) December 7, 2021

There are caveats in those figures – different strength of schedules and Murray’s injury to name but two – but the numbers illustrate the overall point: Quarterbacks have struggled in 2021.

Some of this is an elemental part of the sport, the seesawing nature of offense v defense. Nothing in football is new. Whoever is on the other side of the ball finds a counter. The new idea becomes an old idea. A new one takes hold.

For the past five years, smart teams have taken tried-and-trusted concepts that work at the pro-level and paired them with new ideas that emanated out of college football’s enlightenment period. The age of pace-and-space came to the pros and the league hasn’t looked back since. Pair savvy structures with the most dynamic players to ever play the most important position, and you get something approaching football nirvana.

The Chiefs and Packers torched fools with such structures. While over in Buffalo, San Francisco and Tennessee, quarterbacks that had spotty starts to their careers were suddenly elevated into MVP candidates or at least hit the Quarterback You Can Win With ceiling. The middle strand of quarterback talent was lifted to new heights; the best went places few could have conceived as recently as the 2010s.

This season, defenses have fought back. Teams have shifted en masse to two-deep safety coverages, keeping as many men back as possible for as long as possible. The strategy is intended to cut off deep shots down the field. By doing so, they’re daring pass-heavy teams that are built to play through their quarterback to run the ball or to drive down the field in small chunks rather than go for huge gains through the air. Offenses are left with a tricky choice: To remove the ball from the quarterback’s hand altogether or to ask a batch of off-script freelancers to perform perfectly in 15 play increments.

Defenses want opponents to take 10-20 plays per possession, hoping they’ll turn the ball over or make a mistake before they’re able to score. Are Mahomes and Rodgers willing to take easy, short passes rather than hang around for something to develop down the field? Will Justin Herbert or Joe Burrow get antsy, wanting to indulge their bombs away side? That’s the gamble defenses have made.

It’s a more conservative style, but it has worked. Some of the league’s most prolific scoring machines have become stuck in the mud. The only answer: To run the ball more, something that is anathema to some of the game’s most forward-thinking offensive minds and that requires a perfect 11-man ballet to execute rather than the individual brilliance of the quarterback.

Offenses shifting to a more run-focused plan is in and of itself a win for a great majority of the league’s defenses. There’s a reason that in a season that calls for defensive ingenuity, quarterback efficiency, and run-game diversity that Bill Belichick and the Patriots find themselves at the top of the AFC.

To win this year’s title a team will have to run the ball well enough to force defenses out of their two-deep shells, creeping an extra defender up to the line of scrimmage to stop the run. The league’s most effective offenses are already adapting. No prizes for guessing that the Cardinals, Patriots, and Packers, three Super Bowl favorites, rank in the top-six in run-game EPA per play so far this season. The Bucs, the defending champions, sit in 10th.

Last year’s Bucs were as well-rounded a champion as the league has produced. Offense, defense, special teams … you name it, they did it at a high level. It’s why bringing back everyone from that year’s group was so essential.

It’s going to take a similarly well-built team to rip through the playoffs this go around. There will be no hiding place for a team elevated purely by the brilliance of the most important player on the field.

The natural cycle of the NFL has swung back in favor of the defense, evening out the playing field. Now, it’s time for the sport’s top offensive minds to find counters to the counters. And the best answer might just be the oldest of them all: Line-up the big guys and run the ball.