Greg Cosell's Film Study: Dak Prescott and Trevor Siemian are learning

Dak Prescott had 227 yards in his NFL debut (AP)
Dak Prescott had 227 yards in his NFL debut. (AP)

I wanted to take a look at two quarterbacks who made their first starts in Week 1: Trevor Siemian of the Denver Broncos and Dak Prescott of the Dallas Cowboys.

Both teams used a game plan to put their young quarterbacks in comfortable situations. Prescott is a rookie and Siemian saw only one snap, a kneel-down, last year as a rookie. But both of them also missed some chances at big plays, though that’s to be expected for inexperienced quarterbacks.

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Let’s break down how each of them did.

TREVOR SIEMIAN

The Broncos started their game against the Carolina Panthers with five consecutive passes. Broncos coach Gary Kubiak was trying to get execution confidence for Siemian.

Kubiak also did some things to help out Siemian. He used a quick snap count on each of the first two series, which makes things simpler for a quarterback because it limits defensive movement and adjustment. Kubiak started Siemian with simple concepts, eventually expanding in the third quarter to deeper routes and more combination route concepts. That gave Siemian a chance to make some defined throws downfield.

It’s not surprising Siemian missed some things in his first start. On his second play, the Broncos had a well-designed switch release with a natural rub concept, with Emmanuel Sanders from the slot coming wide open on the wheel route behind Cody Latimer. But Siemian didn’t process it, even though it was open, and threw incomplete to his check-down in the flat.

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Siemian had issues with what he was seeing and not seeing. Another great example was a sack in the red zone on Denver’s second possession. The design of the play was to Jordan Taylor on a “bang 8” route against single-high safety coverage. Siemian didn’t have a feel for controlling the safety with his head and eyes. He didn’t pull the trigger on this throw.

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Here’s what I liked: Kubiak had Siemian come back to the “bang 8” route right away in the second half, and he hit Demaryius Thomas for 23 yards against the Panthers’ “Cover 3” zone. He threw this one with good timing and anticipation.

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Kubiak had Siemian throw on the first play of the series after his first interception; Kubiak did the same thing in the preseason too.

Siemian also showed good poise. From an empty backfield, Panthers tackle Star Lotulelei got through unblocked. Siemian had good poise and awareness to get it quickly to C.J. Anderson on a slide route, and a missed tackle led to a big gain.

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Siemian looked as one would expect. At times he was slow to recognize and process. He was at his best in the quick game, with defined reads and throws. He was mostly poised and composed, and Kubiak tried to help him with play action and basic route concepts. Given the circumstances of a tough opponent and being in his first start, Siemian played well.

DAK PRESCOTT

As we talked about with Siemian, Prescott missed some plays that were there for him. That’s not unusual for a young quarterback, but it’s also the drawback of having a young quarterback starting for you.

Let’s go to the final minute of the game, because Prescott had a big play opportunity and didn’t see it. He had Cole Beasley running clean down the seam when New York Giants rookie safety Darian Thompson busted his “Cover 2” zone responsibility.

What Prescott didn’t process was that Thompson made a mistake and rotated into the deep middle. In “Cover 2,” that left Beasley’s seam route wide open. A more experienced quarterback might have identified that mistake and had a big play to Beasley. He was wide open. Prescott threw incomplete instead.

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The Cowboys also featured three vertical routes with a back-side drag as a complementary route. This was a staple concept. There were opportunities for big plays out of this look and Prescott missed them. The best example came in the first quarter, when Prescott went to the drag route to Jason Witten for just 8 yards even though he had Beasley open on a skinny post. The Cowboys settled for a field goal that drive.

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Prescott did some good things too, and the Cowboys used concepts that Prescott was used to. They incorporated shotgun run action, which was a foundation of Prescott’s game at Mississippi State. Prescott never played fast or rushed himself. He looked comfortable through the game, and what stood out was his patience in the pocket. His feet and body were calm, he was mostly decisive and mostly accurate. Those are all encouraging and promising signs. He also has the ability to sit on his back foot in the pocket and drive the ball with velocity.

Here was a nice throw that Prescott made on the move. The Cowboys called a play-action bootleg with a crossing route by Witten. Prescott made a precisely accurate throw to Witten as he worked against Giants safety Landon Collins.

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The Cowboys catered to what Prescott did in college, which you could see on their 29 first-down snaps. Of those 29 snaps, 16 came with Prescott in shotgun, and there were 22 snaps with one back and seven in an empty backfield. Even though Dallas talked about getting back to the 2014 run-heavy offense, they had 17 passes and 12 runs on first down. The Cowboys did a lot of things that Prescott was familiar with, and he played pretty well.

While both of these young quarterbacks did some good things, and the respective coaching staffs were smart with their game plans, we could also see that there is always a learning curve with young quarterbacks.

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NFL analyst and NFL Films senior producer Greg Cosell watches as much NFL game film as anyone. Throughout the season, Cosell will join Shutdown Corner to share his observations on the teams, schemes and personnel from around the league.