Far too many fans take the details of defending the run for granted. No matter how much football has trended toward the pass, your defense must ALWAYS be built around how you stop the run. Because an effective run game allows offenses to control possession, stay out of unfavorable down and distance, easily move the football, and even create some explosives, the foundation of your defense needs to always allow you to make the run inefficient. If your defense is good in obvious dropback situations but struggles against the run, you will play teams that can stay out of them because they’re in 3rd and 2 all the time.