The 49ers couldn’t be happier with how Jimmy Garoppolo performed in his first full season as a starter. He completed nearly 70% of his passes, threw 27 touchdowns, finished with a 102.0 passer rating, and performed well in critical moments. However, he was also somewhat prone to throwing it to the other team, finishing the season with 13 interceptions. You can bet Steve Spagnuolo will try to find ways to confuse Garoppolo and force some ill-advised throws on Sunday.

Spagnuolo does a great job of using disguise, both from a pressure and coverage standpoint. And he has the perfect player to carry out his vision on the field in safety Tyrann Mathieu. The below interception from Kansas City’s Week 11 win against the Chargers is a great example.

This was 3^rd-and-8. The Chiefs lined up against L.A.’s 3×1 set in a 2-deep look with Mathieu as one of the deep safeties.

At the snap, Mathieu stepped up underneath and the other deep safety, Juan Thornhill (#22), rotated towards the middle of the field.

This made the coverage look like a cover-3 variation, with Mathieu ready to take the #3 inside receiver’s route. Below you can see his initial movement as well as the Chargers’ route combination.

But it turned out that the Chiefs were not playing 3-deep. Thornhill kept running to the other side of the field. Safety Rashad Fenton (#27), who had aligned underneath at first, raced to cover the deep half of the field towards the top of the screen. The Chiefs were actually playing cover-2. Mathieu’s responsibility was therefore to be ready for any vertical seam route down the middle coming from the strong side of the formation. As a result, he would be letting the #3 inside receiver go and would take away the #2 receiver’s route on this play.

Mathieu played with excellent patience here. He read Philip Rivers’ eyes and waited until the last moment to break on the #2 receiver’s route.

Disguise on top of disguise – the Chiefs started in 2-deep, then rotated to give a single-high look, only to continue rotating to that initial 2-deep coverage when it was all said and done. That’s not something quarterbacks see every day. Here, Spagnuolo was able to bait and fool a 16-year veteran. And Mathieu’s ability to execute helped sell the disguise. Every defensive coordinator in football wishes they had a player like him.

Assuming Jimmy Garoppolo has to throw the ball more than 8 times on Sunday, this is the type of disguise you can expect to see Spagnuolo use to try and create a game-changing play.

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