Stopping Aaron Rodgers wasn't easy to do during the 2011 season, which is why he was able to set the single-season-passer-rating record of 122.5 en route to an MVP season. Rodgers had a brilliant season, but one team laid down the blueprint for how to at least slow down the NFL's best quarterback.
In Week 15, the Green Bay Packers traveled to Kansas City to take on the Chiefs in a game that would be Rodgers' worst outing of the regular season. This game would also provide much of the game plan that the New York Giants used in their playoff defeat of the Packers.
The Chiefs were able to beat Green Bay in a major upset with four keys on the defensive side of the ball.
Key No. 1: Man Coverage
Brandon Flowers had one of his best games against Green Bay. He was matched up on the left side of the defense, taking away the outside receiver for much of the game. On the other side, Brandon Carr was fantastic against Jordy Nelson.
In the image above, you can see the formation right after the snap. Green Bay's receivers are in motion, and the Chiefs have defenders in man coverage immediately. You can tell this is man coverage by the proximity of the defenders to the receivers and their mimicking of the direction the receiver is going.
The ability to play man coverage on the outside opened up every other key for the Kansas City defense. By trusting Flowers and Brandon Carr to do their job on the edge, Kansas City was able to routinely blitz their outside linebackers and let the safeties and middle linebackers roam the middle of the field.
Physical play is needed, but the Chiefs weren't overly active at jamming the Green Bay receivers off the line. Instead, they focused on playing side-by-side with the Packers receivers. And it worked.
Key No. 2: Outside Pass Rush
The Packers dropped back to pass 35 times against the Chiefs. In their 3-4 defense, outside linebackers Tamba Hali and Justin Houston rushed the passer on 32 of those snaps, based on my charting of the game. That's just three times that the two linebackers weren't pressuring Rodgers from the edge.
The video above is a great example of the pressure Hali and Houston put on Rodgers all day. Houston, at the top of the screen, gets a good push before being stopped, but Hali crashes on the bottom and effectively turns the tackle to gain the leverage and opening needed to get a sack.
Saying you need pressure is a gimme, but the right kind of pressure is key. The Chiefs run a 3-4 defense, so the pass rush comes from outside the tackle's unprotected shoulder. Teams in a 4-3 defense can rarely get the outside pressure to overpower and outmaneuver the Green Bay tackles. The 3-4 is the key.
Key No. 3: Spy
Kansas City is fortunate to have a great middle linebacker in Derrick Johnson, who is athletic enough to patrol the middle of the field and break on the ball. This is one of those keys that not many teams can duplicate.
We can see Johnson (No. 58) in the middle of the field here after the snap, watching and waiting for Rodgers to make his move.
Johnson was super active in this game, dropping into coverage on all 35 passing attempts. The Chiefs used him in man and zone coverage, allowing him to flow to the ball and make reads to stump Rodgers.
By spying Rodgers with a fast inside linebacker, you allow your safeties to play deeper and give them room to come up and make plays on the ball. This is important with how often Rodgers likes to throw over the middle on his second or third check-down. Having a linebacker there to flow to the middle makes those late throws all the more dangerous.
Key No. 4: Varying Defensive Fronts
Kansas City mixed up its fronts on any down longer than 10 yards to go. Here we see two different formations, the first on 2nd-and-13 and the last on 3rd-and-13.
The Chiefs are in a three- and then two-man front in these two images taken one play after the other.
The key is that Rodgers and the offensive line cannot get comfortable with their blocking schemes and assignments with an ever-changing front. The 3-4 defense makes this hard enough, as the offensive linemen never know where the pressure will come from. Changing the number of down linemen and linebackers makes this an impossible task.
Not every team will have the right mix of players, coaches and execution to carry out this plan the way the Chiefs and Giants did, but at the very least, this shows where the Packers were weak in 2011 and is a good starting point when looking at how to slow down the NFL's best passing game.