As always, all eyes are on Peyton Manning, but does he have to carry too much of the load in Denver?Andy Lyons/Getty Images

Despite their red-hot start, Peyton Manning and the Denver Broncos have lost their aura of invincibility. They are still the favorites in the AFC, but the loss to the Indianapolis Colts in Week 7 raised some questions about the team. The most important of which being: Can they win if Peyton Manning isn’t perfect?

To be clear, the sky is not falling in Denver. It was one game, and though they have fallen behind the Kansas City Chiefs for the division lead, those Chiefs still have to play the Broncos twice.

Nevertheless, the loss in Indianapolis was disturbing.

It took a fourth-quarter comeback from the Broncos to make the final score as close as it was. The Colts' excellent pass rush and physicality with Denver’s receivers disrupted the timing of a passing offense that had been firing on all cylinders to start the year.

They sacked Manning four times (including the devastating strip-sack by Robert Mathis that resulted in a safety). In addition, the analysts at Pro Football Focus counted six occasions where Manning was hit to go along with 12 quarterback hurries (subscription required).

Week 7 was clearly Manning's worst game of the year.

It speaks volumes about how phenomenal Peyton Manning has been that his Week 7 performance can easily be singled out as his worst game of the year. The man still threw for 386 yards and three touchdowns after all.

But he wasn’t perfect. Manning had been about as perfect as he could be to start the season, putting up historic numbers and a record-setting pace, according to ESPN.

The result was an overpowering Broncos team that looked like it would steamroll its way to the Super Bowl in a weakened AFC.

That juggernaut has lost some of its luster over the past few weeks because some chinks in the armor have been exposed.

The most glaring weakness has been the defense. It hasn’t been the same stellar unit of last year—one that finished as Pro Football Focus’ second-best defense (subscription required).

While the pass coverage has been kept busy due to the high-powered offense demanding opponents try to keep pace, that was also the case last season and the drop-off has been significant.   

Furthermore, they finished last season with 52 sacks, tied for the most in the NFL. That presence hasn't been there this season.

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To be fair, they played the first six games without their best pass-rusher, Von Miller, but they have sorely missed Elvis Dumervil as a complementary pass-rusher (who has 5.5 sacks in his seven games with the Baltimore Ravens).

The good news for the Broncos is that they still have the time and the personnel to improve on defense. Their quest to get better starts this Sunday against a Washington Redskins offense that is starting to get its legs back and put up 499 yards of total offense in Week 7.

While most of the attention might go to the matchup of the devastating Broncos offense against a very poor Washington defense, the more important aspect for Denver is whether their defense looks better. If they don't improve, Denver may once again fall short in the playoffs.

Whatever perspective you have on Jim Irsay's comments in the buildup to last week's game in Indianapolis, one point he made stands out. He told Jarrett Bell of USA Today that the Colts had changed their model because they wanted more than one ring.

While some took that as a shot at Peyton Manning, Irsay claimed he was pointing out the failures of the Colts organization to give him a more balanced team that would have had more success in the playoffs.

Time will tell whether the Broncos are balanced enough, but for right now—just like it was in Indianapolis—Manning will have to carry the team and be perfect for the Broncos to make a serious playoff run and contend for a title.

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