I have been criticizing Army for years for not accounting for the enemy QB on defense. What would I say if they demanded I explain exactly HOW to do that?
The basic answer is on pages 35 to 37 of my book Gap-Air-Mirror Defense. That discussion is about how to stop the off-tackle play, but the same principle applies.
Collingsworth said tonight that the Vikes may have to put a spy on Trubisky. Yeah, that is one possibility, but it is only half the solution. Whomever you choose for spy was doing something else on defense before you made him a spy. What something else are you going to stop defending in order to assign a spy to the QB?
A spy is a defender who just follows the QB on every play. Fine. But all such adjustments are robbing Peter to pay Paul. Figuring out that you have to pay Paul is the easy part. The basic principle of defense is strength against strength. If their QB draw play is a strength, you have to put defensive strength against it. Trubisky has averaged six yards a draw so it is a strength.
What is the offense weak at?
The question is what play is the WEAKNESS of the offense. That is the Peter you have to rob to pay the QB draw Paul. What is that in this game? I do not know. I look for that in film study and go into a game with the Peter identified for each weakness in my defense that may be discovered during a game.
I did not do any pre-game film study of the Bears. Essentially, your spy or whatever technique you use needs to weaken you where the offense is also weak. Your spy would likely be a different player from the defender currently up against the weak spot. For example, you might assign an agile DB type guy to be a spy and take out a run-game linebacker to do that.
Not the only fix
And spy is not the only fix for QB draw. You might give two or three defenders an additional duty or a specific lane-controlling path to take in their rush.