Denver Broncos quarterback Peyton Manning and Green Bay's Aaron Rodgers may be the big names in this matchup, but defenses will decide who wins.

Doug Pensinger & Thearon W. Henderson/Getty Images

When the NFL schedule was released in the offseason, Packers at Broncos on the first weekend of November figured to be one of the best games of the fall. Aaron Rodgers vs. Peyton Manning chatter would presumably lead the charge. But predicting that this would be a matchup of the two defenses allowing the fewest amount of points in the NFL through seven weeks of the NFL season wasn't realistic.

Yet here we are.

More from FoxSports

While the Broncos offense has looked good enough -- but south of stellar -- the Packers offense has been a MacGyver unit, becoming increasingly more resourceful despite the loss of three of their best offensive players. Pro Bowl wide receiver Jordy Nelson was lost for the season to an ACL injury, running back Eddie Lacy has been slowed and lightly used with an ankle injury, and wide receiver Davante Adams hasn't played since Sept. 28 against the Chiefs. Adams figures to return against Denver.

During that time of depth chart challenges, the Packers have settled into an approach behind their elite quarterback that illuminates three absolute "musts" for any defense facing them. The work the Broncos have done against lesser offenses has been impressive, but if they don't ace these three areas against the Packers, a winning result is highly unlikely.

FRONT THE POCKET

There are a handful of mobile quarterbacks around the NFL that can gash you with their feet. Not rushing upfield past the quarterback is an obvious requirement against all of them. But beyond just closing the walls around Rodgers, the Broncos can't make the mistakes of many other defenses: leaving the front door open.

To study Rodgers' mobility in the pocket is to observe high-level football art. Time after time, he allows the rush to develop, keeping his eyes downfield, only to reset into the soft spot and deliver his dart. As a pass rusher, understanding that he's simply waiting for you to declare a side on your respective blocker (so that he can slide the opposite way) to deliver his throws is paramount.

Defenses that have not had a body directly in front of the pocket when Rodgers looks to deliver his throws have been torched repeatedly either with open throwing or scramble lanes. Most four-man rushes stay evenly distributed with two rushers on each side of center, but this typically leaves a hole somewhere over the ball for Rodgers to take off when the coverage clears.

The following example shows an initially balanced defensive line with a linebacker fronting the pocket to close that escape route. But when that linebacker's coverage removes him from the box and all four rushers work up the field, that's the soft spot Rodgers so often takes for huge chunks of freebie yards (below).

What exacerbates this situation is one of the unintended consequences of a depleted group of receiving weapons for Green Bay. Without obvious mismatches in receiving personnel, teams have felt more comfortable playing man-to-man across the board against the Packers. Man-to-man defense usually means the coverage players will have their backs to the quarterback, unable to see Rodgers as he scrambles to that path of least resistance at the front of the pocket.

The Broncos have the skilled coverage personnel in cornerbacks Aqib Talib, Chris Harris, and Bradley Roby to feel they can live in man-to-man defense against most teams. But if they do so and don't close that front door in the pocket, Rodgers will inevitably take their lunch through giveaway scrambles.

The Broncos would be well-served to devise a scheme where one of their interior defensive linemen powers the middle of the pocket over center without picking a side. A fronted pocket when playing man-to-man defense is infinitely more important than chasing that handful of elusive sacks you might get throughout the course of a game against the Packers.

CATCH AND RUN ... AND RUN SOME MORE

If there's one aspect of the game that will be most telling for the Packers offense, it is the amount of run-after-the-catch yardage they accumulate over the course of a game. Green Bay has thrived on catch-and-run plays -- simple route concepts or screen schemes that get the ball in the hands of play-makers.

Wide receivers James Jones, Randall Cobb, and the aforementioned Adams thrive with the ball in their hands in space more so than creating separation downfield in their routes. The Packers use a healthy amount of screen game and quick passing to help highlight these traits and manufacture big-play threats through plays that start as small ones (below).

The onus here will be on Broncos defensive backs to tackle quickly in the open field, and for linebackers and safeties playing the role of next-man-in to rally quickly, take good angles and wisely use their leveraged help in pursuit.

The downfield chunk play attempts will come from the Packers -- often on first down -- but the real big-play threats from the Packers offense as it's now configured will come from turning the mundane into bigger problems. If the Broncos can suffocate the catch-and-run opportunities, it plays heavily to their favor as the Packers will be forced to look for bigger bites down the field where the talented Broncos secondary can really plaster their individual coverage responsibilities.

BALL DISRUPTION

Sacking Aaron Rodgers is the purple unicorn of defensive game-planning. Disrupting his passing lanes to make every throw as difficult as possible? Not nearly as unrealistic. There comes a time in every pass rusher's day where he has to make a decision. The St. Louis Rams were one of the few teams this season to make a healthy amount of the right ones, and force Rodgers into a less-than-stellar day (see below).

The decisions of the Broncos rusher who happens to be in the line of sight for Rodgers' intended throws may be one of the most important aspects of the entire defensive performance for Denver. This is something you see all the time in the NFL -- there's always that moment when a rusher realizes the quarterback is preparing to make a throw.

If in that instant they rush to take a side on their respective blocker instead of using their length to provide an obstacle to the throw, the quarterback gets off easy with a clear path to his target.

Rodgers is just too good of a thrower to allow clean lanes to his receivers. If Broncos rushers play smart and make the choice to power their blockers and get a hand up when the throw is imminent, they can clog the throwing lanes and make life infinitely more difficult for Rodgers. If not ...

It's easy for me to sit here and write all the things you have to do to slow the Packers offense -- the hard part is executing. That said, if the Broncos defense doesn't front the pocket in their pass rush, tackles poorly in the open field, and doesn't err on the side of ball disruption over something less likely, don't be surprised if another big day is on the horizon for the Green Bay offense.

STORIES FROM FOOTBALL BY FOOTBALL

Matt Chatham played for the Patriots and Jets over nine seasons in the NFL, winning three Super Bowls. He is also the founder of footballbyfootball.com. You can follow him on Twitter.