Footwork is the most critical component to the play of a quarterback. Working from under center provides a passer with a sense of rhythm and timing that makes a passing game go. When a quarterback hits his third, fifth or seventh step, his eyes are geared to work in unison with the progression of each route, allowing a passer to set quickly and dump the ball if he sees a blitz coming on his first step or hit his seventh step and uncork it to a deep layer.

In the shotgun, a quarterback’s footwork is not natural. As defenses are shifting into coverage from disguised looks, a shotgun passer must drop his eyes from reading the field to catching the ball and back to the field again while turning his body and getting into throwing position. In that fraction of a second, as a quarterback is looking to get the grip on the ball and redirect his eyes, a lot can happen. Disguised coverages can show and already tight windows can close. On Sunday, Colts OLB Robert Mathis fell back into coverage against the Lions in that short span, directly into Matthew Stafford’s throwing lane. However, the fourth-year passer never saw Mathis as he caught the ball from the shotgun snap and immediately whipped a pass toward Brandon Pettigrew. The result was an easy interception for Mathis.

The integrity of quarterbacking mechanics has slipped in the NFL this season, and one of the chief culprits has been the proliferation of spread, shotgun offenses. Peyton Manning and Tom Brady can shift their feet quickly from the gun, but their mechanics are well-drilled from more than a decade of work and they are two of the game’s all-time great technicians. For younger quarterbacks such as Stafford, Jay Cutler, Cam Newton and even Aaron Rodgers, who started off the season very slowly, the prevalence of shotgun attacks has begun to erode NFL passing games, destroy the mechanics of its passers and diminish the quality of the product on the field.