What the Tape Saw: Denver’s overtime touchdown was a triumph of play design

We've been talking all through the second half of the season about Denver Broncos offensive coordinator Mike McCoy, and the impressive adaptations he's set in motion to predetermine success for Tim Tebow in what is a slightly unconventional offense at the NFL level. With various strains of option runs and spread passes, Denver's offense with Tebow at the helm is an interesting cross-section of ideas. What it hadn't been to date, at least not consistently, was effective in the passing game.

That all changed in the Broncos' 29-23 wild-card win over the Pittsburgh Steelers, and I thought it would be interesting and instructive to go back and break down the 80-yard pass from Tim Tebow to Demaryius Thomas that ended the game on the first play of overtime. As limited as Tebow has been as a passer, this design was an outstanding exhibition of faith by McCoy in his young quarterback, and a lesson for one veteran cornerback on the other side.

It's always hard to discern coverage unless you know for sure what the intention was — players blow assignments and there are disguises to throw even the more savvy viewer off — but this looked to me like another example of the deep cross the Broncos have been able to use in specific circumstances through the season with success. When Tebow is passing well and still brings the threat of the run (as he did through the second half), the play action forces the intermediate defenders to come up in run fits, which delays their coverage assignments just long enough to get started with the route concept that takes a bit more time.

What this looks like is that the Steelers were playing inverted cover-2 (where the safeties play deep and the cornerbacks come up in closer coverage, but drop as safeties come up to deal with intermediate pass and closer run responsibilities. I was able to confirm this coverage with Stanford Routt of the Raiders, who saw the Broncos twice this year, and who has explained advanced coverage concepts to us before.

Inverted Cover-2 is an effective method of confusing a quarterback who doesn't see the alteration coming (Chris Brown of Smart Football has an excellent explanation of the Robber concept in different fronts and coverages right here) … but in this case, it left the Steelers in a bit of a pickle.

Pre-snap, free safety Ryan Mundy came down in the "Robber" look, obviously to read whether the Broncos were going to run. The playfake to running back Willis McGahee was a great call here (especially out of shotgun) because the move up to the inside run fit was predetermined. At the snap, and as Thomas ran the deep cross from left to right, Taylor shifted out to outside position to cover him, and Mundy was a step late to cover underneath as he read the fake.

"It's a play that we ran earlier in the night," Broncos head coach John Fox said. "We had a pretty good tendency of running on first-and-10, and they utilized some zero-blitz stuff. I think we executed in that situation."

That single step was all Thomas needed to run the post route and catch the ball at the left hashmark. He beat Taylor from inside, and had the speed edge on Mundy in intermediate coverage. From there, it was off to the races, and the touchdown that sent Denver into a pandemonium.

"We were on the sideline and talking about it before we even went out there on the field and we were like, 'We are going to run this play and all you have to do is beat the corner,' Thomas said of the big play. "They said, 'All you have to do is cross the safety's face and I was walking to the line and saw the safety come down and I knew, at that time, the play that we had called, the only person I had to beat was the corner. I crossed his face and I knew the middle of the field was wide open."

The mistake was Taylor's — he should have kept inside position in that instance. This wasn't a case of Mundy inadvertently biting on the run — in this coverage, he was doing what he was supposed to do. As Routt told me, it's one of the weaknesses of the coverage when you disguise it as the Steelers did.

"We called underneath coverage, and I was underneath," Mundy said after the fact. "Ike [Taylor] was over the top. I've got to watch the film, but I felt like I could have given him a little more help underneath. That was particularly our run-stopping defense, so I've just got to watch the film but I feel like I could have given more help."

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