Even if he’s not at the top of his game, Peyton Manning and the Broncos are a serious threat to win the AFC. (Ron Chenoy/USA TODAY Sports)

Saying that the NFL stands for Not For Long has become cliché at this point, but its cliché because it is true in so many ways. Health, success and schematic advantage are all fleeting in a sport where more players impact the outcome of a game than any other. Even knowing that, it’s almost impossible to believe that the Broncos – the owner of arguably the best defense in the league this season – are only a mere two seasons removed from setting the all-time record for points scored in a season.

That was ages ago though by NFL standards. Gone are Eric Decker, Wes Welker, Julius Thomas, Knowshon Moreno, Zane Beadles, Manny Ramirez, Orlando Franklin, and for a while Peyton Manning himself. But even with an extreme offensive regression and below average play from the most important position on the field, quarterback, this team still the No. 1 seed in the AFC. They have four different players grading in the top five of their position on this defense. And they are as healthy as any team in the AFC. The Broncos are a sleeping giant in the race for Super Bowl 50.

The Divisional Round

The two most impactful names featured on the injury report for this weekend’s games both belong to Steelers. Ben Roethlisberger and Antonio Brown hooked up 16 times for 189 yards and two touchdowns in their Week 15 win against Denver. The status of both for Sunday’s game is completely up in the air as of Thursday.  Brown is going through the concussion protocol after a brutal hit from Vontaze Burfict last weekend while Roethlisberger suffered an AC sprain and multiple torn ligaments in his throwing shoulder, also at the hands of Burfict. If both are anything other than fully healthy on Sunday, it will completely mitigate the Steelers’ personnel advantages from their previous meeting.

In that memorable late-season matchup Pittsburgh dropped back to pass a ridiculous 62 times. The Broncos defense played man coverage on 45 of those snaps, as high a rate as you’ll see in the NFL. When you play man-coverage though, you’re betting that your defensive backs are more talented than the opposition’s receivers, and that was far from the case that day.

I wouldn’t bank on Wade Phillips completely altering his game plan this time around though. While the Steelers receivers were getting separation, there were a ton of tight windows that were threaded by Big Ben. Even if he is able to play with his injury, there is no doubt his accuracy – especially downfield – will take a hit. Phillips also knows that Roethlisberger was phenomenal this season when given time in the pocket. On 126 dropbacks when facing the blitz, Roethlisberger had a completion percentage of 56.8, averaged 6.2 yards per attempt and threw seven touchdowns against six interceptions for a quarterback rating of 73.9. On his 367 other dropbacks, Roethlisberger had a completion percentage of 71.8, averaged 9.2 yards per attempt, and threw 14 touchdowns compared to 10 interceptions for a quarterback rating of 101.5.

A completely healthy Denver defense that graded out in the top three for run defense, pass coverage, and pass rushing should be all the Broncos need against a hampered Steelers offense.

The AFC Championship

If the Broncos are able to get past the Steelers at home, they’d host either the Patriots or the Chiefs for the right to go to the Super Bowl. While both New England and Kansas City have offensive lines that rank in the bottom three for pass-blocking, something the Broncos can exploit, this one will all be on Peyton Manning’s right arm. While the Steelers have done well for themselves by ball-hawking this season with 17 interceptions, they are still one of the bottom-10 teams in PFF’s pass coverage grades. The Patriots and Chiefs on the other hand are second and fourth respectively.

In that magical 2013 season, Manning was accurate on 48.2 percent of his passes targeted 20-plus yards downfield, the second highest rate in the league, and gained 1,299 yards on 38 completions, both the most in the league. This year though, his 28.6 accuracy percentage on deep balls was the third worst of any quarterback and he managed only 438 yards on 10 completions.

That being said, Manning’s accuracy and performance this season varied wildly from game to game. He would flash for a game or two, like Green Bay and Detroit early on, and look like the old Peyton, throwing in rhythm to the correct receiver play after play. Then there were disasters, like the second matchup with Kansas City, where it looked like he forgot how to play quarterback.

It’s difficult to believe that the injury to his foot didn’t play some considerable part in his decline this year though. His previous three seasons in Denver he made a turnover-worthy throw on 3.0 percent of his attempts. This season that number skyrocketed to 5.7 percent. Manning’s arm strength has been nonexistent ever since he came to Denver, but one would imagine his decision making wouldn’t all of a sudden fall of a cliff as well.

If Manning is truly healthy and can finally run plays from under center, thus opening up the full playbook for Gary Kubiak, the Broncos have to be considered the favorite to come out of the AFC.

Mike Renner is a writer for Pro Football Focus and a contributor to The Washington Post’s NFL coverage.

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