It’s only Week 2, but the stakes are high in this intra-division battle between the Chicago Bears and Minnesota Vikings. The former has a chance to shoot to the top of the division with a win, while the latter could have its season over before its even begun.

It’s the fourth quarter and they’re deadlocked at 24. Jay Cutler is in control at the line of scrimmage, which is the 40-yard line, singling out the middle linebacker (“MIKE IS 50!”) and pointing out the safeties. He does this each time before the snap to help sort out pass protection for his offensive line and make a mental image of what to expect from┬áthe secondary after the snap. There’s two deep safeties, one of which is Harrison Smith, who a year ago intercepted Cutler and took it to the house for six in a similar situation.

Cutler stands over the center and barks out another command. “ONE-EIGHTY!” Then he quickly crouches under center and yells “READY! HUT!” and takes a five step drop.

At the top of the drop, he keeps his feet busy, shuffling them around as he climbs the pocket before launching the ball in the direction of Marshall.

Marshall’s running an outside developing route that sees him initially run straight ahead at Smith and then expand to the sideline. He’s essentially using the real estate that Alshon Jeffery, who’s running a square-in five yards from the line of scrimmage, won’t be. He’s also attempting to stretch Smith wide and give room to the tight end, Martellus Bennett, who’s running down the seam. This is two verticals, and it can be an undisciplined safety’s worst nightmare.

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Smith has his work cutout for him. Marshall’s a big body at 6’4″ and 230 pounds. He has an incredibly strong upper half that’s lethal when combined with his outstanding body control. Bennett is no different, running down the seam at 6’6″ and 265 pounds. Both are big targets that can make even the correct decision wrong.

The key is to keep the distance split between the receivers. In Cover 2, a five under, two deep zone coverage, the safety’s landmark is in between the numbers and the hashmark, keeping the distance equal between the two and, ideally, the two vertical threats. It also doesn’t give the quarterback a tip to the direction he should throw in.

If a backpedal is being used, the shoulders should be squared throughout the technique and the safety should only commit once the ball has been thrown.

But Smith’s not using the backpedal on this play. He abandoned it at the snap, preferring to turn his hips and face his body towards Marshall, and the sideline’s direction. There’s nothing wrong with shuffling through the play because he is still in a position to defend both vertical threats. If the ball is thrown to Marshall, he can plant and drive on it for a potential interception. If it goes to Bennett, he can turn up and inside to cover the outside of the tight end.

As he zips into coverage, Smith is aware of responsibilities. At this point it’s clear that he has to either commit to Marshall or Bennett once the ball is in flight. He confirms that when he goes through his keys, which require him to look at Marshall and Jeffery’s routes and then back at the quarterback.

Cutler’s made the decision early on for Smith: the ball is going to Marshall. Now it’s up to Smith to shuffle over, take the correct angle, and wrestle the ball away for a potentially game-changing turnover.

It’s not easy to take a proper angle on the ball. Every week a safety takes a wrong angle, cutting it too short and consequently watching the ball fly over his head. It’s one of the most important fundamentals of the position, and it’s thoroughly stressed in Cover 2, which requires the safety to cover half of the field and frequently expand his zone to a vertical running receiver.

Smith is rangy and intelligent, using his speed smartly. He does this at a high level, which shows once again here.

Watching the ball leave Cutler’s right hand and sail through the Windy City air, Smith is poised to intercept it. Ten yards into his shuffle, he widens out to the numbers with Marshall. He continues to widen while Marshall slows down and appears to settle at the 15-yard line to haul in the pass. At the 10-yard line, Smith sinks his left cleat into the Soldier Field grass and swings his arms to propel himself toward the receiver and break on the ball.

He takes an intersecting angle, anticipating the ball to land at the 11-yard line outside of the numbers. There he leaps and reaches for the ball with his excessively padded and outstretched arms to intercept it in front of Marshall. He taps his left foot in, then the right. For good measure, he taps the left again.

Jay Cutler is no longer in control.