When the Bears and Packers open the 2019 NFL season on Thursday Night, there will be a lot of new faces on the field and the sidelines. But the Bears Offense and Packers Defense should both look similar to their 2018 versions, at least schematically. At its core, this will still be a Matt Nagy/Mark Helfrich vs. Mike Pettine game on this side of the ball.

Both of these units were evenly matched last season. Neither overwhelmed the other. The same will likely be true on Thursday, meaning this matchup will come down to which team can make plays during those critical moments of the game. 3rd down, therefore, is key.

3rd down is when defensive coordinators love to pull out all the stops. They love to disguise coverages, bring blitzes, and force the offense to have to make a play to beat them. Packers Defensive Coordinator Mike Pettine is no exception to this rule. In fact, he was able to fool Mitch Trubisky and the Bears Offense multiple times in 2018 with late movement and disguise. Several times, the Packers won early in the down. Several times, however, they failed to contain Mitch Trubisky.

The below play is a perfect example. This was 3rd-and-10. At first glance, this appeared to be some kind of single-high coverage. Perhaps it would be cover-3. Perhaps it would be man coverage.

At the snap, the deep safety made an initial move to the center of the field (bluffing a single-high look) before racing back to the far sideline. The Packers were actually playing cover-2 to the three-receiver side of the field.

Additionally, take a look at the many other defenders showing one look initially before executing another after the snap:

The underneath safety started in the middle of the field, but then raced over to the 3-receiver side to become the curl-defender. The linebacker showing a blitz on the line of scrimmage dropped into coverage and became the Tampa-2 middle linebacker carrying the deep middle route. The two defenders aligned in the slot, presumably in coverage, blitzed at the snap.

Below, you can see the play up until a couple of beats after the top of Trubisky’s drop:

At this point, the disguise had worked. It not only prevented Trubisky from getting to the optimal play against the coverage pre-snap, but it took away the routes Trubisky was looking for post-snap. You can see from the end zone angle below that Trubisky was not calmly working through his progressions. There was some uneasiness, and the muddled picture quickly left him looking at the pass rush.

Schematically, the defense won here. However, the pass rush did not get home, and the Packers failed to contain Trubisky. He was able to escape and run 14 yards for the first down. You can see the full play from both the sideline and end zone angles below.

We saw this multiple times during their two head-to-head matchups in 2018; A disguise that worked early in the down, only to have Trubisky scramble and make a play.

The 3rd-and-7 below is another great example. The Packers were able to bring a 4-man pressure that got a free runner in on Trubisky. The defense won this play schematically again. The Bears won the down, though, as Trubisky was able to evade the pass rush and find his receiver for 23 yards off a scramble.

In their week 1 matchup, the Packers had similar problems. On the below play, another 3rd-and-7, the Packers were showing blitz with five men on the line of scrimmage. At the snap, however, two defenders dropped into coverage. This was actually a 3-man rush.

Green Bay was able to take away the three-receiver route combination to Trubisky’s right. Schematically, the Packers once again won the down.

The Bears would once again end up winning the play, though. Trubisky avoided the pass rush and immediately fled the pocket, recognizing that the design of the play was taken away by the coverage. The Packers again let Trubisky scramble to the outside, where he is at his best. The result was another 3rd-down conversion.

None of this is to say that the Bears Offense was outstanding on 3rd down against Green Bay in 2018. In their two games, the Packers held Chicago to 10 third-down conversions on 27 tries (37%). That’s slightly below the Bears’ season average.

Yet this is the crux of the matchup on this side of the ball. In a game of two evenly-matched units, making plays in critical moments can determine the outcome of the game. The Packers showed the ability to fool Trubisky and keep the design of Matt Nagy’s plays from working on the money down. They failed to always execute and keep Trubisky from using his legs to make plays, though.

The Packers would be wise to employ a mush rush against Trubisky on Thursday night. Their edge rushers have to make sure they don’t attack too far upfield to provide escape lanes, or too far inside to allow access to the perimeter. If Green Bay can find a way to keep Trubisky in the pocket consistently, the advantage on this side of the ball should swing in their favor.