Sunday's NFC Championship Game will not be the first time that the San Francisco 49ers and Green Bay Packers have squared off this season. In a Week 12 prime-time game in Santa Clara, the 49ers bludgeoned the Packers 37-8, sending the visitors back to Wisconsin with their third and final regular-season loss. Although both teams finished the year with the same 13-3 record, the Packers appear just as outclassed now as they were two months ago.
Above all else, Green Bay's failure to generate any semblance of a passing offense was their downfall. In fact, per DVOA, the Packers' Week 12 match against the 49ers defense was their second-worst passing performance of the season, trailing only a three-turnover performance in a defense-dominated victory over Minnesota in Week 16. Quarterback Aaron Rodgers was held to just 104 yards on 33 passing attempts (3.2 yards per attempt) while being sacked five times for 38 yards. While he did not give up an interception to the 49ers' turnover-happy defense, Rodgers was rendered a complete non-factor.
In fairness to the future Hall of Fame quarterback, the Packers' receivers dropped a few critical passes. Geronimo Allison dropped a third-down pass over the middle, Marquez Valdes-Scantling failed to drag his feet in bounds when trying to catch a ball in the back of the end zone, and Jimmy Graham dropped a downfield strike that Rodgers threw while rolling out of the pocket. Still, even if all of those plays had converted, it would not have been enough to entirely salvage this game for Green Bay.
Plenty of factors culminated in the 49ers' dominance over Rodgers, but perhaps none were more influential than their ability to take away the middle of the field. Only two of Rodgers' 33 pass attempts fell between the painted numbers in the 5- to 25-yard range on the field. Neither were complete. In that same yardage range, Rodgers only attempted five passes on or outside of the numbers, only one of which was completed. In every sense, the middle of the field was a complete wasteland for the Packers offense.
San Francisco's linebackers can be credited for that. While the 49ers have Pro Bowl talent at every level of the defense, they may have the best coverage linebackers in the league. Against play-action, in particular, their linebackers are fantastic at reading out the fake and getting back into their assignments. As a result, the 49ers were able to finish with the best play-action defense in the league, holding opponents to just 6.0 yards per play on play-action passes (subscription required). Conversely, Green Bay's offense only managed a 27th-ranked 6.7 yards per pass on play-action despite having the 13th-highest usage rate. Smash together San Francisco's strength and a Green Bay weakness, and it's no wonder Rodgers looked like Derek Carr playing at Arrowhead.
Here the 49ers are in a Cover-3 call with the strong safety rolling down to be a flat defender. On the other side of the ball, the Packers motion out of a tight bunch set, then boot to the right with a flood call. This is a standard play-action rollout that every single team in the league runs one way or another. In San Francisco's particular coverage versus what becomes a 2x2 set, the hook defender opposite the deep crosser is responsible for executing roll-and-run technique (a.k.a. robot technique) to find the crosser and take it away. On this play, that hook defender is undrafted rookie Azeez Al-Shaair (51). As soon as Al-Shaair sees Rodgers start to roll out, he instantly flips his hips to turn and run under where he assumes the crosser is going to be. Al-Shaair executes the technique well, getting under the crossing tight end early on in the play and sticking tight with him the whole way through. Rodgers had no chance of throwing the crosser here.
This time, the "robot" hook defender changes because of how Green Bay is choosing to flood one side of the field. In the first clip, the Packers only had three players to one side of the field, but in this example, they bring four, adding an extra shallow receiver for Rodgers to check down to. The extra receiver forces the coverage to "push" to that side. Dre Greenlaw (57), another rookie, becomes the "robot" hook defender as Fred Warner (54) moves toward the two underneath receivers. While Greenlaw comes off the route a bit prematurely at the end, he did well to turn and find the route early to cloud Rodgers' vision of the throwing lane. Greenlaw managed to deter Rodgers for just long enough to squeeze the route tight to the sideline, making this throw much more difficult than it's supposed to be.
Here is Greenlaw taking out another crosser, this time from the opposite side of the crosser against Minnesota. As Nate Tice identified in a Twitter post earlier this week, the 49ers are in match-coverage version of Cover-3. Like in the first play, the hook defender opposite the crosser (Greenlaw) is responsible for robot-ing to find the crosser and run with it. It takes Greenlaw a second to register the play concept before having a lightbulb moment, as Tice refers to it, and turning to sprint toward the deep crosser. Greenlaw's raw speed allows him to make up the gap from his slight delay, putting him in position to make Kirk Cousins just uneasy enough about the throwing window to instead opt for the checkdown. Warner, the other hook defender, rallies toward the checkdown in a hurry and stops it for just a 4-yard gain.
San Francisco's linebackers can do more than just robot, though. Defenses do not become the best in the league without having linebackers who are, at the very least, above average as coverage defenders. Warner, the literal centerpiece of the 49ers defense, may be the league's best coverage linebacker right now.
Before the snap, Warner is lined up smack dead between the hashes, which puts him on the inside shoulder of the tight end. The tight end, in this instance, is the No. 3 (innermost) receiver to a trey (trips with a tight end) set. San Francisco look to be in some form of 2-Man, which makes Warner responsible for No. 3 wherever he goes. As the ball is snapped, Warner immediately turns his back away from the sideline and looks to drive on the tight end breaking toward the outside. The tight end breaks inside, though, forcing Warner to flip his hips completely. Warner makes the speed turn in an instant and immediately drives toward the tight end's inside (left) shoulder so as to undercut any pass thrown that way. Shooting straight for the undercut coming out of a speed turn requires a special blend of athleticism, technique, and bravado. Warner pulls it off to perfection and forces Cousins to check down once again, which results in a drop by the running back.
Green Bay does not have a clear answer to San Francisco's lockdown of the middle of the field. Davante Adams is the only wide receiver on the team who can consistently win his routes, but he is going to struggle to do so when matched up against Richard Sherman. As far as tight ends go, Graham is middling and no longer poses the same threat between the 20s that he used to, while Marcedes Lewis has a case as the league's slowest pass-catcher. The Packers tried to go checkdown- and quick pass-heavy in their last showdown, but the 49ers defense rallies and tackles exceptionally well, so even that fell flat most of the time.
It is going to take a previously unseen collapse at the heart of San Francisco's defense for Green Bay to come out on top here. Even Minnesota, who boasts significantly better tight ends than Green Bay as well as a second legitimate wide receiver, failed to crack the 49ers' middle-of-the-field defense; it is tough to imagine this Packers offense is going to be able to do so. The Packers can still find ways to pull off the upset, but attacking the 49ers pass defense over the middle, specifically their linebackers, is not one of them.