If he doesn't win his appeal and is suspended for the first four games of the 2013 NFL season, then Manning and his offensive teammates will be put to the test early.
First reported by ESPN's Adam Schefter, the NFL has issued a four-game ban against Miller, who will appeal the suspension in mid-August:
It's worth noting that Miller has denied doing anything wrong, as noted by NFL.com's Marc Sessler, and that Manning and his fellow teammates "have his back," as noted by Michelle Beisner of NFL Network:
Losing Miller won't doom Denver's 2013 campaign—not by a long shot.
The Broncos are going to win the AFC West and contend for the Lombardi Trophy—with or without Miller's suspension. This team will be a force to be reckoned with in the playoffs, at which time Miller and his potential suspension will be nothing more than a footnote.
But if he is out for the first four games, then Denver's offense will be put in a position where it must score a bunch of points to win games.
There's no denying Miller's extraordinary impact on the team's defense.
Rated the No. 1 4-3 outside linebacker by Pro Football Focus last year (subscription required), Miller is the kind of player that opposing teams must account for on every single snap.
He's one of the most disruptive pass-rushers at any position in the league, having logged 18.5 sacks, 15 additional quarterback hits and 52 quarterback hurries last year.
His ability to bring pressure significantly improves the chances of success for his teammates in the secondary.
If he misses time, veteran free-agent acquisition Shaun Phillips will likely be the man to play in his stead.
As a starter for the Chargers last season, he managed to pile up 9.5 sacks but was a highly ineffective overall player. PFF rated Phillips as its second-worst 3-4 outside linebacker with score of negative-21.
Phillips' best days are clearly behind him, though he still has value as a situation pass-rusher.
Combined with the loss of Elvis Dumervil, Denver's defense will likely struggle mightily to pressure opposing quarterbacks. Miller and "Doom" combined for 29.5 of the team's 52 total sacks last year.
Even the best of secondaries is prone to exploitation by quarterbacks who have time to progress through their reads and set their feet.
And the Broncos secondary, while not bad, certainly isn't among the best in the NFL.
With teams like the Baltimore Ravens, New York Giants and Philadelphia Eagles on the schedule during the first four games of the season, Denver's defense could find itself over-matched without Miller in the lineup.
This would, in turn, put more pressure on Manning and the rest of the team's offensive starters to come together quickly and play at a high level early in the season.
With a new receiver in Wes Welker and a new starting running back that has yet to be determined, it's not a given that the Broncos will start out hot on offense, either.
Don't get me wrong.
You'd be foolish to bet against Manning.
He'll certainly have himself and his teammates in the best possible position to thrive right out of the gates this season—just like he has every year since he came into the league in 1998.
But don't get it twisted.
Losing Miller will mean the Broncos must score more points to win games, which puts the onus on Manning and his teammates to show up big early on.
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