It's true that the Saints broke up with Adrian Peterson because it just wasn't working out. But like with many breakups, it was also because someone else had entered the picture. In this case, someone younger and more exciting than Peterson: Alvin Kamara, recipient of head coach Sean Payton’s publicly revealed “man crush.”

Kamara, a third-round rookie from Tennessee, embodies the evolving NFL skill position player. Averaging 6.3 yards a carry, he’s quick and agile enough to create his own space as a runner. He’s a dynamic receiver, capable not just of aligning anywhere in a formation but winning as a route runner. Put a weapon like Kamara in an offense designed by a mad scientist like Payton and quarterbacked by a machine like Drew Brees, and sparks fly. The Saints have had this before: Darren Sproles, from 2011-13. But Kamara will be an even more integral contributor because of how the league is changing.

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The chasm of athletic difference between defensive linemen and offensive linemen is greater than ever and still growing. At the same time, rule changes have favored wide receivers in their matchups with defensive backs. And because practice time has become so limited, those with reactionary duties—like blockers reacting to pass rushers, or defensive backs reacting to receivers—are falling further behind. It all adds up to an increased emphasis on quick-strike passing. A quarterback must throw the ball before his blockers break down and before extra defenders can arrive to help the overmatched defensive backs cover his receiver.

A quick game only achieves consistency if your quarterback can identify the defense before the snap. (Reading the defense only after the snap results in the ball taking too long to get out.) This is one reason guys like Kamara are so valuable. When Kamara aligns in the slot or out wide, the defense's response tips the coverage. Brees knows, for example, that if a linebacker follows Kamara out wide, it's man coverage (since linebackers are generally who cover backfield players). If Kamara goes to the slot or out wide and a cornerback is across from him, it's zone, with that corner having simply stayed home. Sometimes, just to get this information, an offense will put players in motion. (Ever noticed how the Chargers, for example, initially split their running back out wide and then motion him into his usual backfield spot?)

The formation most conducive to all of this is “Empty,” with just the QB in the backfield and everyone else flanked out, usually in spread spacing. The Saints do this as much as any team. The beauty of Empty is, not only does the running back’s location and defensive response reveal man or zone coverage, but in spread, the quarterback can often decipher what type of man or zone coverage. Because when the offense spreads, so must the defense. The farther away defenders are from each other, the harder it is to rotate into different coverages after the snap. There’s simply too much ground to cover, especially if the defense believes the ball is coming out quickly (which, in Empty, it usually does, given that offensive linemen are left to block those more-athletic defensive linemen one-on-one).

You don't necessarily need a weapon like Kamara to make this work. Last season, the Falcons frequently split fullback Patrick DiMarco out wide in Empty, simply to research the defense’s response. (It’s worth noting that Atlanta’s struggling offense this season has done less of this with fullback Derrick Coleman.) DiMarco wasn’t a threat, but when he was on the field, it was always with running back Devonta Freeman or Tevin Coleman—two flexible players, like Kamara. With two backs and Atlanta's potent zone running game, defenses would be in base 3-4 or 4-3 personnel. And so the spread Empty formation forced at least one linebacker to play at a de facto cornerback location. That created a mismatch that favored Freeman or Tevin Coleman.

Kamara presents this dimension. At times, he’s on the field with running back Mark Ingram. And, of course, the Saints can control matchups with their backs through other formations besides just Empty. New Orleans has long been cutting edge here, as Payton likes to present 15 different formations in his first 15 scripted plays. The idea is you show the defense as much as possible so that the defense shows you as much as possible. The Saints examine the defensive response to each formation and determine their play-calling from there. They can also intellectually overwhelm the defense in this process; it’s hard to contend with 15 looks on 15 plays, especially early in the game, before much rhythm is established. Naturally, the Saints are often among the league's most productive opening drive teams.

The more versatile your personnel, the more dimensional your formation becomes. And there’s a domino effect, as an ultra-flexible player like Kamara amplifies everyone’s versatility since where he lines up can create favorable matchups for teammates.

Flexible formationing has been around for decades, but there simply aren’t many players with the versatility to make it lethal. Not coincidentally, the teams with smart, veteran quarterbacks tend to be the ones that have the best flexible weapons. (Chicken or egg?) There’s James White with Tom Brady. Le’Veon Bell with Ben Roethlisberger. Tyreek Hill and Travis Kelce (the league’s only super-flex tight end) with Alex Smith. There are the Atlanta backs, Freeman and Coleman, with Matt Ryan. Theo Riddick with Matthew Stafford. Ty Montgomery and Randall Cobb with Aaron Rodgers (though not for the next couple months, of course). And when both were healthy, David Johnson with Carson Palmer.

There are also a small few who don’t play with an established quarterback. The most notable is the one who will be on the sideline opposite Kamara this Sunday: Chicago’s Tarik Cohen. The fourth-round rookie is even more electrifying than Kamara, but he plays in an offense with a callow rookie QB (Mitchell Trubisky) and a bunch of third-and fourth-string wide receivers.

There’s also Christian McCaffrey, whom the Panthers drafted eighth overall to headline conversations like these. McCaffrey is panning out fine, but Carolina’s offense is not evolving around him the way New Orleans’s is around Kamara. With Cam Newton, a tremendous power thrower but inconsistent precision passer, the Panthers remain more of a downfield passing team as opposed to a spread, quick-strike one. McCaffrey is becoming a screen and checkdown weapon, not unlike a Giovani Bernard or LeSean McCoy. You can still create matchup problems with him, especially if you employ pre-snap motion as effectively as Carolina has. But expanding all route concepts—particularly the spread ones—is more difficult.

The word football coaches use all the time is “matchups.” The more versatility you have, particularly at running back, the more you can dictate matchups. Players like Kamara, paired with innovative coaches like Payton and field general quarterbacks like Brees create the matchups that spur football’s evolution.

Film Note Elaboration

This probably needs to be an entire article, but oh well, I have no problem saying it again and again each week. Tom Brady has been around much longer than I’ve been watching film, so grain of salt here, but: This season has provided the most impressive Brady film that I’ve ever seen.

Cause for concern?

Terrelle Pryor, who signed a one-year deal with Washington this offseason, was demoted to wide receiver No. 4 Monday night at Philadelphia. Pryor’s route running, which improved dramatically over the course of last season in Cleveland, has regressed. He has also struggling to catch the ball. Washington has managed to get by with its talented receivers lagging (2016 first-rounder Josh Doctson, too, has floundered, though he appears to be slowly turning things around), but this team won’t make the playoffs if it continues. Jay Gruden’s intricate route combinations hinge on perimeter receivers winning deep and on in-breaking patterns. It can’t be all Jordan Reed, Vernon Davis down the seams and Chris Thompson catching backfield screens.

Keep an eye on

Bengals 2016 first-round corner William Jackson III. He’s been stellar playing around 15 snaps a game on the right side in Cincy’s cornerback rotation. Last week at Pittsburgh, Jackson filled in for an injured Adam Jones and won a variety of one-on-one battles, including some against Antonio Brown. Jackson has the size and transitional movement skills to be a premium outside corner. Given how inconsistent Jones has become, it’s time for a fulltime change here.

Injury Impact

The notion that Miami’s offense got on track against the Jets once Jay Cutler cracked his ribs and Matt Moore came in is false. Miami’s passing game had come back to life from the get-go; Moore simply continued what Cutler started. (The film and statistics clearly bear this out.) That said, head coach Adam Gase will have a tough decision to make if Moore plays well against the Ravens Thursday night. Overall, Cutler has had a poor season. His mechanics have been erratic (that will always be true) and he hasn’t compensated for Miami’s up-and-down pass protection. We could debate what are fair expectations for a QB plagued by bad surroundings—Gase almost always gives the benefit of the doubt here; he’s not one to heap blame on a quarterback. My sense is Moore will have to light it up for Gase to make a permanent change under center.

Non-football thing on my mind

When did people start saying “brah” instead of bro? And how have they ever been allowed to get away with either? Calling someone “brother” is already tenuous; you walk a fine line between endearment and condescension. Abbreviating the term almost always pushes you over the wrong side of that line (especially on Twitter, where condescension goes to breed).

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