Aqib Talib was sitting in the stands, taking it all in.

He sat with Denver faithful, catching his breath and beaming after a 103-yard pick-6 that put the icing on the metaphorical cake that was the Denver Broncos’ 42-17 utter destruction of the Dallas Cowboys.

Dez Bryant was sitting on the bench, taking it all in.

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He sat by himself, exasperated, staring into the distance — who knows where? — and in disbelief of what had just happened. As soon as the ball hit Talib’s hands on that play, Bryant might as well have walked off the field and taken his spot on the bench. For all we know, he might have.

He, much like the Dallas Cowboys as a whole, couldn’t do anything to stop the Denver Broncos on Sunday afternoon.

***

The 2016 season was really very simple for the Cowboys. They ran the ball as well as anyone. They controlled the clock. Their quarterback hardly ever turned the ball over because he rarely had to force anything down the field, and opponents had to fear — not respect, fear — the run game. It was a straightforward route to success, a route they rode to a 13-3 regular-season record.

It’s also a route they veered off of on Sunday afternoon against the Broncos, who punked the Cowboys up front on both sides of the ball. It wasn’t only a frustrating loss, but one that exposed a lot of potential issues for Dallas.

The numbers aren’t pretty: Ezekiel Elliott ran for eight yards. His previous low was 51, which came in his NFL debut, which his team also lost. The Cowboys lost the time-of-possession battle by nearly eight minutes. They converted three of 14 on third down, while the Broncos converted nine of 15, including seven straight at one defining point of the contest.

There are two big issues, and they go hand-in-hand. The first: The Cowboys couldn’t run the ball — a tenet upon which they are built — so their offense couldn’t stay on the field.

Denver struggled to stop the run last year and made moves this offseason — the addition of monstrous defensive tackle Domata Peko chief among them — to address that problem. His presence and impact was immense as a simple space-eater. The holes Elliott so often and so easily found in his rookie year weren’t there on Sunday. Instead, he found the arms of Peko, Derek Wolfe, Von Miller and others who were more than happy to wrestle him to the Mile High turf.

And Dak Prescott struggled in the face of a ferocious pass rush and perhaps the league’s best secondary. It brought back memories of his 2016 struggles against a similarly talented defense, the New York Giants, against whom he went 0-2, completed just half his passes and tossed one touchdown and two interceptions last year. He only threw four picks all of last season.

One big reason for Prescott’s success last year was his performance in play action — an area where Pro Football Focus rated him best in the NFL. But when the run game presents little to no threat — as Dallas’ did — the play action isn’t nearly as effective. And when four players can win at the line of scrimmage — as Denver’s did — there’s no reason to commit extra guys to any concept the opponent may run.

Then there’s issue No. 2: the defensive problems, which were often masked by a dominant offense last year. The Cowboys whiffed on tackle after tackle. They missed assignments. They lost one-on-one matchups. Trevor Siemian looked like John Elway, C.J. Anderson like Terrell Davis.

Before Sunday, the Broncos had cracked the 30-point barrier just once — 34 points against Indianapolis in Week 2 of last season — under Siemian. Against Dallas, Siemian and company exploded for 42. Siemian, who most people view (perhaps correctly) as the underwhelming but safe choice over Paxton Lynch, made two mistakes on Sunday: an early fumble and later a pick on a play that was a miscommunication from the start. Other than that, he picked apart Dallas’ defense with short- and medium-yardage passes. He posted a quarterback rating of over 114 when targeting Demaryius Thomas and Emmanuel Sanders. If the Cowboys had a gameplan to limit Denver’s two most proven weapons on the outside, they certainly didn’t execute that plan.

And that’s without mentioning Anderson, who seemed to be a forgotten man after an injury-shortened 2016. If anyone needed a reminder as to who he is — or how good he is — they got it on Sunday. Anderson showed his terrific all-around game, getting to the edge, running behind his line, going around or through defenders and making an impact in the passing game. That Denver converted 60 percent of its third downs with a quarterback who is widely viewed as a game manager is concerning. That the Cowboys couldn’t contain the three best playmakers Denver has is, well, choose your own adjective.

The good for the Cowboys? It’s early. These are issues that can be fixed, and with the talent on the roster — especially on the offensive side of things — they should be fixed. But with the Dallas offense unable to stay on the field and the Dallas defense unable to get off it, there’s ample reason to be perturbed for now.

The look on Dez Bryant’s face as Aqib Talib celebrated will tell you as much.

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