by Derrik Klassen

Lackluster performances do not always have to spell future disaster. When the Los Angeles Rams had their passing offense dampened by the Detroit Lions two weeks ago, it felt like little more than the Rams stepping on a small thorn on their way to the promised land. The Lions set a quality blueprint by surrendering the flat area to motion men and not allowing the Rams to beat them deep, but much of Los Angeles' passing struggles in that game also came down to Jared Goff posting one of his worst personal performances of the year. Given the team's three months of dominance to start this season, in addition to how well they fared a year ago, a stumble against Detroit seemed like something Los Angeles could overcome without issue.

Then the Rams packed up and went to Soldier Field to face the Chicago Bears. The Bears, already alone at the top Football Outsiders' defensive rankings, took the Lions' game plan and upped the ante, both in creativity and in raw defensive talent. By the end of the 60-minute contest on Sunday Night Football, the Rams had posted their worst offensive DVOA rating (-47.5%) of the McVay era (not including Week 17 last season when the starting lineup was resting on the bench). In a year when good offenses have regularly won out over comparable defenses, the Bears' defense flipped the script.

Critical to the Bears' success was taking away the vertical seams. Dating back to his days in Washington, McVay's vertical concepts have been centered around attacking through the seams with tight formations. Bears defensive coordinator Vic Fangio turned to an abundance of tight two-deep shells to counter McVay's affinity for vertical shots through the seams. Doing so immediately capped the seams vertically, and Fangio trusted his cornerbacks to keep up on the outside to allow this idea to work.

The Rams are in a tight formation with the passing strength on the right side toward the boundary. On the other side of the ball, the Bears' two deep safeties are aligned 10 yards off the ball and just wide of the offensive tackles. Putting the safeties in this position pre-snap takes away the Rams' ability to slip into the seams early on and would allow for the Bears to easily match them down the field if they dared to go there. Additionally, being only 10 yards off the ball enables the safeties to play the run aggressively and also close on intermediate crossing routes or in-breaking routes over the middle, all of which directly counters what the Rams want to accomplish with these formations.

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As intended, Goff is steered away from the vertical route down the seam. Chicago's two safeties backpedal for a few steps at the snap to pressure Goff away from the vertical shot, then clamp down on the crossing route as soon as Goff makes the decision to throw in that direction. Goff made a poor throw regardless of the coverage, but the concept of restricting Goff's ability to take shots and look elsewhere paid off throughout the game for Chicago. In fact, the Bears held the Rams to just one throw of 20 or more yards. From Weeks 1 to 12 (11 games plus bye week), the Rams had 57 such plays, roughly five per game.

What also stood out from Fangio's game plan was how much he trusted the skill sets of his cornerbacks. Prince Amukamara's press coverage strengths and Kyle Fuller's skill in zone schemes were used in tandem to create combo coverages that the Rams were not ready for.

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Take this pass breakup by Amukamara, for example. Amukamara is in tight press coverage to the top of the screen, while Fuller (23) retreats to an 8x1-yard alignment off the wide receiver right before the snap. As the play gets rolling, Fuller backpedals for another 5 yards or so before sinking his hips to play off of Josh Reynolds' (83) route break. Amukamara, on the other side of the field, carries his receiver in press coverage to about 10 yards before closing on the receiver's route break and jumping in front of the throw, nearly intercepting it. This was not the first time this game that Goff tried to throw an interception at Amukamara, and it would not be the last.

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Here is another clip of the Bears using the same strategy. Like in the last example, Amukamara (bottom) is in press coverage and Fuller (top) is in off coverage. However, this play is a little different because rather than being in the middle of the field, the ball is on the left hash, meaning Fuller has more ground to cover in his coverage assignment. Fangio does not worry about Fuller's range or ability to make up ground through route recognition, though, and allows Fuller to play by himself on that half of the field. Fuller makes sure to stay on top of wide receiver Robert Woods (17) and not allow him to get vertical, while Amukamara slows down Brandin Cooks (12) through his route enough to deter Goff from making the throw. Goff is then stuck at the top of his drop with nobody to throw to, allowing a blitzing Danny Trevathan (59) to hit Goff and force him to throw the ball away.

An underrated aspect of this play for Chicago is how their two deep safeties rotate down to fill the 6- to 12-yard area that the linebackers may normally patrol. This allows the linebackers to follow the play-action through the backfield and act as blitzers. More often than not, defenses will have their safeties in more conservative assignments and ask the linebackers to trail back into coverage after play-action, giving Goff time in the pocket and a clear window over the middle of the field. The Bears allowed precious little of that to happen to them.

As the cherry on top, Fangio made it a point to bring blitzers from tricky positions. The week prior, Matt Patricia and the Lions had some success blitzing the Rams' tight formations with defensive backs and getting quick pressure. With an even better defensive line to accentuate it, the Bears took up the same approach.

In more balanced or spread out formations, blitzing from the wide side of the field with a defensive back is difficult. There is simply too much ground to cover and a more spread out defense to expose. When the Rams condense the formation and bring the nickel cornerback to the middle of the field, however, the defensive back then has much less ground to cover and the receivers have less room inside to abuse his absence. Fangio exploited that principle by bringing Sherrick McManus (27, orange circle) on the following play.

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Chicago rotates to a match Cover-3 fire zone blitz, which deploys three deep defenders and three underneath/middle defenders. At the snap of the ball, the Bears' defensive line stunts to the left and draws the blockers to McManus' side to funnel inside. McManus gets a free run into the backfield as result of the stunt and meets teammate Leonard Floyd (94) at the quarterback, ending in yet another hurried and helpless throw from Goff.

The key to Chicago's performance is how well they blended each unique aspect of their game plan together. On nearly every play, the Bears found a way to maximize their cornerbacks' skill sets, take away the deep seams through safety alignments, and generate creative pressure all at once. Each individual concept was effective by itself, but when perfectly blended together, the Bears' defense morphed into a no-fly zone against one of the best passing offenses in the league.

The Bears' showing should not be watered down by the idea that McVay should have simply ran the ball with Gurley more, either. Fangio crafted a handful of unique fronts to shut down the Rams' rushing offense, particularly in overloading the weak side of the formation with defensive linemen to take away the Rams' coveted weak zone run. Gurley was kept down for most of the contest. Moreover, the passing offense was such a trainwreck that Gurley would have needed a transcendent night to make up the difference. Counting on that caliber of play, even for as talented as Gurley is, is a fool's errand and McVay knew it.

After stomping a juggernaut Rams' offense, the Bears' defense now holds the No. 1 defensive DVOA spot by nearly double the rating of the second-place Baltimore Ravens. Chicago's performance on Sunday night was no fluke, it was a confirmation that they have the best defense in the league and are capable of taking down the league's most explosive offenses.