Late Monday night, as the football world reckoned with the Kansas City Chiefs-Los Angeles Rams smorgasbord, the notion that no defense had been played became a common and easy refrain. The teams had combined for 105 points. The offenses gained 1,001 yards. The quarterbacks threw 10 touchdown passes. It was a futuristic offensive masterpiece and, by traditional measures, a futile defensive disaster.

Viewed through another prism, one quickly gaining currency around the league, the Rams and Chiefs had played defense exactly as the modern game demands. The Rams forced five turnovers and scored two defensive touchdowns. The Chiefs forced two turnovers and scored once on defense themselves. Rules and innovation have conspired to make defenses helpless over sustained drives against the best offenses. The best way to succeed on defense may be to make one or two massive plays of your own.

“For me, from a defensive traditionalist, which I think most defensive coaches are, that’s a hard thing to admit to,” said Steve Spagnuolo, a former NFL defensive coordinator and head coach who is taking this year off. “But … these offenses that are scoring a lot of points are doing it because they’re explosive in nature. Your [new] conventional wisdom is matching explosive plays with defensive explosive plays.”

Rams-Chiefs was both exceptional and a window into how NFL defenses may be forced to operate. This season, 37.5 percent of drives have ended in a score, the highest mark ever by nearly two percent. In 1999, the first year Pro Football Reference has data for, teams scored on only 29.2 percent of drives.

Teams gain 4.4 yards per rush, the highest on record. They gain 7.5 yards per pass attempt, the highest mark since 1962, when quarterbacks completed 53 percent of their passes and 6 percent of their throws were intercepted. This year, completion percentage is at an all-time high (65.2) and only 2.4 percent of passes are picked off. Overall, teams gain 5.7 yards per play, which is — guess what? — the highest mark on record.

“The worst job, or the toughest job, in coaching nowadays is the defensive coordinator,” said former Oregon defensive coordinator Nick Aliotti, who watched firsthand as the offensive concepts taking over the NFL now overwhelmed college defenses last decade, including those of then-Ducks coach Chip Kelly. “It’s just a thankless, tough job. Offenses spread you out so much. All the rules, almost every rule, is offensive-driven. It’s very, very difficult to be a defensive coach in today’s football game.”

The league facilitates offense through rule changes. Skill players entering the league now, owing to the rise of seven-on-seven youth leagues, have played more football than any players before them, but their defensive counterparts spent none of that time learning to tackle. Former NFL coach Mike Shanahan has said technology allows the brightest offensive ideas to spread faster and easier, and that flow of information benefits offense more than defense. The NFL has fully embraced concepts that supercharged college offenses over the last two decades; last year, Air Raid impresario and Washington State Coach Mike Leach said of the New England Patriots, “Their offense looks like ours.”

Add all those factors together, and defensive attrition is no longer a sound strategy. For years, defenses could play to bend but not break. In 2018, when defenses bend, they break. Their best recourse is to make the offense break first. Playing defense is no longer trench warfare. It’s special ops.

“Gotta make those turnovers,” New England Patriots safety Duron Harmon told the Boston Herald. “When you’re going against an offense like K.C., you know they’re going to make some plays. They’re an explosive offense. But you’ve got to do something on defense to limit them, and [the Rams] did that with the turnovers.”

As a defensive coordinator, Spagnuolo charted all kinds of performance indicators for his players. One category he listed was labeled MOBP — missed opportunity for big play. That category, he said, has more and more importance, while traditional measures of a defense’s proficiency have grown less relevant.

“A bogus stat in today’s football is defensive total yards allowed,” Spagnuolo said. “To me, playing good defense comes down to situational defense — third down, red zone, any two-minute [situation]. … When you have an opportunity to make a big play, you have to make it.”

The defensive imperative to create big plays has already been showcased at the sport’s apex. In the Super Bowl last year, the Patriots scored 33 points and never punted. Yet the Eagles won the game with their defense: Brandon Graham’s strip-sack of Tom Brady in the final minutes sealed victory. One play can undo 59 minutes of yielding yards and points. Monday night, the Rams and Chiefs took that lesson to the extreme.

“Welcome to the new NFL when it comes to defensive football,” former Patriots linebacker Tedy Bruschi wrote Monday night on Twitter. “Offenses will move the ball and score. Make a handful of plays a game to take the ball away and get your offense a couple extra possessions.” Bruschi, who starred during an era of more traditional defensive football, added, “It hurt to write that.”

Watching Rams-Chiefs was, unquestionably, a ludicrously thrilling experience. But if such offense predominates, will the effect for a viewer wear off? Kids lose their minds on Christmas because there are presents strewn on the living room floor only one morning a year.

“I’ve talked to friends of mine,” Spagnuolo said. “NBA basketball, you watch the last four minutes. Somebody in the last four minutes either makes the last shot or makes a big steal. I hope football is not becoming like that. I hope our game is not going to become score, score, score, score and then when it gets down to the last four minutes, let’s watch football.”

Maybe it will become an issue, but then again, people seem to love college football. For a brief period at the level, only a few teams ran offenses similar to, or borrowing from, Leach’s Air Raid or Kelly’s Blur. In less than a decade, those systems became the norm. Aliotti expects the same thing is about to happen in the NFL. Teams may not be as proficient or as talented as the Rams, Chiefs and Saints, but they will copy them, and franchises will seek players and coaches who can execute and implement similar systems.

“Absolutely,” Aliotti said. “Things are cyclical, and that’s the trend right now. You watched that game [Monday] night, and you go: ‘My goodness. How do you stop those teams?’”

If we are glimpsing the future of offense, then what might the future of defense look like? Aliotti said he sees a rise in hybrid defensive players — linemen who can drop into coverage, linebackers comfortable rushing the passer or taking on responsibilities similar to a safety, “long, lean players and guys that can play in space.”

Collecting interchangeable players will allow defenses to fool offensive linemen and quarterbacks. More importantly, Aliotti said, fluidity between linebackers and the secondary confuses wide receivers, which limits how effectively quarterbacks and wideouts can communicate at the line of scrimmage or read coverages after the snap.

Spagnuolo once stopped an unstoppable offense. In Super Bowl XLII, the undefeated 2007 New England Patriots, the greatest offense anyone had ever seen, scored only twice in a 17-14 loss. Spagnuolo’s plan relied on rushing Brady with four defensive linemen, using their individual brilliance and creative stunts and rushes.

The problem is offenses today rely heavily on screens, pop passes and short throws that negate a pass rush. The fierce pass rush the Giants used to upset the Patriots in the Super Bowl — a combination of ideal personnel and savvy design — would probably be the best weapon against one of this season’s modern, pyrotechnic offenses. The Rams beat Kansas City in part because of big plays made by pass rushers Aaron Donald and Samson Ebukam. But it also probably still wouldn’t keep the Chiefs or Saints from lighting up the scoreboard.

Spagnuolo, a self-proclaimed defensive traditionalist, plans to return to coaching next season. He was only half-kidding when he laid out his personal solution to today’s scoring binge.

“I’m really thinking about going back on offense,” he said.

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