The Denver Broncos schedule has no gimmes, and this Sunday against the Dallas Cowboys will be a huge test for the Broncos new coaching staff. After a solid win against the typically-underachieving Los Angeles Chargers, the Broncos face a team that went 14-2 last year and just beat the New York Giants to a pulp—the only team that beat them in the 2016 regular season.

The Cowboys are going to be a real test for Denver’s vaunted defense and for the Broncos new-look, Mike-McCoy-led offense. As we prepare for this barometer of a game, here’s what to look for and some matchups that the Broncos can exploit, plus just about any other information you may need from a, Xs and Os standpoint before kickoff on Sunday.

Offense

The Cowboys present a unique challenge with their talented offense that’s at its best running the ball thanks to star running back Ezekiel Elliott and the NFL’s best offensive line. The Broncos defense has been historically great against the pass, led by its dominant pass rush and the “No Fly Zone” but stopping the run’s been different which is why Dallas will be quite hard to stop.

If you want an even fight with the Cowboys, it all starts with the ground game. Stop their run and everything changes, allow them to run and they’ll slowly beat you into submission. That’s much easier said than done, as Dallas rushed for an average of 150 yards per game last season (second best in the league) and picked up where they left off in Week 1, running over the Giants for 129 yards.

It’s not simply stopping the run, but it’s everything that comes with it that makes Dallas’ offense so dangerous, and part of that is how lethal Dak Prescott can be in play-action situations. This is where the Cowboys attack is most dangerous, and it’s where their quarterback can often get out into space on bootlegs and make things happen with his feet. Dallas’ offense used play action 24-percent of the time last season, third-most in the NFL.

Containing Prescott and forcing him to beat you with his arm is another key to the game as his poise is superb and his ability to improvise plays or make tough throws on the run is also noteworthy. Trying to stop all of that while having to overcome Dallas’ talented offensive line is especially difficult and could be even for Von Miller and company.

Forcing Dak to beat the “No Fly Zone” straight up with his arm is the key, while giving him as little time as possible and trying to keep him in the pocket.

Prescott doesn’t just scramble to pass, but he can also hurt you as a runner, something Denver will have to be ready for particularly in short down-and-distance situations. Dallas is especially dangerous in RPO (run-pass option) plays in short yardage where their offensive talent makes them especially tough to stop. Keeping a linebacker or even a safety up close to the line to “spy” on Prescott from time to time might not be a terrible defensive adjustment in an attempt to add pressure and limit Dak as a runner.

Dallas has Dez Bryant at receiver, who’ll be lined up a lot against Aqib Talib in this game, but their more dangerous receiving targets—especially for Denver—will be tight end Justin Witten and slot receiver Cole Beasley. Limiting their chances and covering those two safety blankets is crucial.

Denver’s struggles with tight ends are known though they did a phenomenal job against the Chargers two talented ends last week. Continuing success in that area will be crucial, as will limiting the impact of stacked formations with multiple tight ends that the Cowboys do use from time to time.

Jason Garett and his staff like to operate out of a lot of standard three-wide formations—especially off balance, allowing Dak to have simpler reads—with Witten and Elliot, and they have lots of success. This won’t be much about Xs and Os but more lining up and being able to withstand the ground game and force Dak to beat you on your terms and not the Cowboys’.

Elliot himself will also present a tough challenge for linebackers who have to tackle him in space and when he’s used as a receiver where he has reliable hands and can be a true danger.

Simply put this will be as tough a challenge as the Broncos have faced on defense in the last few seasons.

Matchup to watch for Broncos

Cowboys RT La’el Collins against Von Miller

Yes, the Cowboys offensive line is loaded with talent, probably the best of which is left tackle Tyron Smith who’ll be a helluva match up for Shaquil Barrett. On the other side is Collins, whose talent is unquestioned but has limited experience starting at tackle in the NFL and will get a heavy dose of Von Miller coming his way on the strong side.

Miller was blocked incessantly with double, and at times triple, teams Week 1. Dallas will likely stick to their plan and see how Collins handles Miller with some help from Witten. If Von can dominate and put pressure on Prescott consistently, everything will become easier, and while the Cowboys offensive line deserves all the respect they can get, make no mistake, Miller versus Collins is a matchup that strongly favors Denver. It’s also worth noting that the ‘Boys line isn’t as dominant pass protecting as they are run blocking as they allowed a sack rate of 6.5 percent last season, good for 12th worst in the NFL (per football outsiders). They’re good, but they’re also human.

Sticking to the offensive line, after a great game Monday night, Shelby Harris could be a secret weapon lined up over left guard, the Cowboys’ weakest spot on the line.

Defense

The Cowboys defense isn’t an NFL-best type unit, but they’ve quietly been really good the last two seasons.

The Cowboys success on D has come much in the same way that their offenses has—all on the ground. While they might not have big name pass rushers or defensive backs, Dallas dominated teams against the run in 2016 to the tune of 83.5 yards allowed and continued that trend Week 1 holding New York to 35 yards on the ground.

They do all that while bringing very little added pressure on blitzes and having Rod Marinelli’s defensive mind scheming the back end. The chess match of Marinelli versus McCoy will be very interesting.

The Broncos ability to run might not be crucial, but it’ll be important to keep the opposing ‘D’ off balance, something Denver did very well with the Chargers.

While they don’t like to bring added pressure with linebackers or safeties, the Cowboys do have a talented and slowly-developing core of pass rushers led by Demarcus Lawrence, who sacked Eli Manning twice in Week 1. His speed and athleticism will present a good test for the Broncos OT’s. Rookie Taco Charlton in addition to Charles Tapper forms a rotation at defensive end that’s heavily relied on to create pressure by Dallas.

The Cowboys have talent at linebacker with Sean Lee and Jaylon Smith, who are athletic and can cover, but similar to LA, Denver will have to test those backers in coverage with tight end packages and even trying to get Jamaal Charles in space.

The secondary is where the Cowboys can really be attacked, which means Trevor Siemian, Demaryius Thomas, and Emmanuel Sanders will have to be up for the task. Particularly strong safety, Jeff Heath can be exploited, and the Cowboys cornerbacks are young, they have to be attacked.

Matchup to watch for Broncos

DT and Emmanuel against the Cowboys cornerbacks

DT looked back to his old ways against Los Angeles, while Sanders barely missed a couple of touchdowns that could have completely turned his night around. That was against Casey Hayward and Jason Verrett, not Nolan Carroll, Anthony Brown, and the other youngsters. The Broncos have to win the matchups in which they’re favored, and this is probably the biggest miss match in Denver’s favor of all.

Of course, pass protection is crucial for this to happen and Siemian will have to be accurate and trust his wideouts to go get the ball when in single coverage on the outside as he did with Thomas Monday Night.

Keys to the game

This’ll be a unique game with a matchup of two teams whose strengths are the other team’s weakness and vice versa. So something will have to give as Von and the “No Fly” face Zeke and the NFL’s best O-line.

That means the Broncos will have to make their strengths count, but it’ll also put pressure on their weak spots. Denver’s run defense will be key, and picking up on the Week 1 performance would be huge, especially if Derek Wolfe’s conditioning is back to 100-percent and Adam Gotsis plays as well as he did a week ago.

On offense, as much as DT and Sanders need to dominate the Cowboys cornerbacks, the run game can’t be absent, and the tight ends and slot receivers will have to be impactful again.

If all goes according to plan, this could very easily come down to Prescott versus Seimian, and who can make plays beyond the Xs and Os. Dak has the edge on paper, but Trevor’s had some moments of magic in his brief career, so don’t sleep on No. 13.