3rd-and-7 at SF 40
On their first third down of the game, the Chiefs use 11 personnel for the first time.
The 49ers are in their nickel defense, with Ahmad Brooks and LEO Elvis Dumervil on the outside of the line, and Arik Armstead and defensive tackle DeForest Buckner on the inside:
Dumervil is in his preferred two-point stance, and is in a very wide 9-technique.
The 49ers’ inside linemen are also wider than a traditional “9339” front:
At the snap, Brooks, Armstead and Dumervil make moves inside toward the quarterback, but Buckner is caught off-balance and is pushed to the outside:
Buckner continues with his outside route to the quarterback, which leaves Smith with a wide lane up the middle; but between Smith and the line to gain, strong safety Eric Reid is policing the middle of the field:
However, Reid leaves the center of the field to pursue receiver Albert Wilson who is loosely followed by cornerback K’Waun Williams, but is nowhere near the first-down marker.
For good measure, Reid then runs the receiver over for a 15-yard penalty:
Smith sees the open field vacated by Reid, and darts upfield for a first down.
Reid’s penalty is tacked on to the end of the play, and the Chiefs have their first shot in the red zone: