Peyton Manning appeared to come alive late in his game with the Chiefs in week 2, as well as his game Sunday night vs the Lions. The Broncos are 3-0, and in control of the AFC West for yet another year. But the fact is, Manning is still not performing nearly as well as he needs to be at the start of the season, because he always sees a precipitous drop in production later in the year.

Manning's performance has now dropped early in the year for another season, and it's been a measurable decline. In the first 3 weeks of each of the last two seasons, whether in passer rating, yards per attempt or completion percentage, Manning has been worse than the prior year. And that becomes a problem because later in the season, he's noticeably worse in all 3 metrics than he is at the start of the season, as the below table indicates:

Additionally, Peyton Manning has shown a decrease in his deep passes, traveling 15+ yds in the air. His current average is only 9.2 ypa on such passes, down from 13.0 in 2013 and 12.2 in 2014's first 3 weeks. Though the 3 week sample size is small, there certainly is more than enough data to raise some flags. We know Manning is adjusting to a new offense under Gary Kubiak, and we know he's working with a new offensive line. But while those excuses could give reason for hope, the above numbers coupled with the following certainly should not be comforting to Broncos fans:

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Cause for Concern

Manning's opposition hasn't been the best --the Ravens, the Chiefs and the Lions so far in 2015:

-The Ravens allowed the Raiders Derek Carr and the Bengals Andy Dalton to complete 50/78 (64%) for 6 TDs, 2 Ints, 9.4 ypa and a 110 rating. Manning went 24/40 (60%) for 0 TDs, 1 Int, 4.4 ypa and a 60 rating.

-The Chiefs allowed the Texans Brian Hoyer/Ryan Mallett combined to complete 26/47 (55%) for 2 TDs, 1 Int, 7.1 ypa and an 83 rating. Aaron Rodgers went 24/35 (69%) for 5 TDs, 0 Int, 9.5 ypa and a 139 rating. Manning went 26/45 (57%) for 3 TDs, 1 Int, 5.7 ypa and an 87 rating.

-The Lions allowed the Chargers Philip Rivers and the Vikings Teddy Bridgewater to complete 49/60 (82%) for 3 TDs, 2 Ints, 9.3 ypa and a 108 rating. Manning went 31/42 (74%) for 7.7 ypa and a 102 rating.

- In virtually every case, when comparing to quarterbacks who faced the same opponents, Peyton Manning performed (at best) equal but most often, measurably worse. And most of these quarterbacks are not considered "equals" to Peyton; we're measuring against Brian Hoyer, Ryan Mallett, Derek Carr, Andy Dalton and Teddy Bridgewater.

The Broncos offensive health isn't likely to improve. Much is made about the Broncos offensive line needing time to "gel" and work together. But one thing is certain--currently everyone is healthy. And that includes his starting receivers, tight ends and running back. And most of all, it includes Peyton Manning. That's something which isn't likely to continue all year. As I wrote in March, the Denver Broncos were the healthiest overall team in 2014 according to Football Outsiders adjusted-games-lost metric. But in 2013, they ranked 25th (the 8th most-injured team). It's highly unlikely they will remain as healthy as they were in 2014.

Reason for Hope

The Broncos defense should keep the Broncos in most games. The Denver defense is holding opponents to 4.25 yds/play (best in the NFL). On an average play, opponents gain first downs on 25.1% of plays vs Denver, the 3rd best in the NFL (only the Cardinals and Jets have been better). It boils down to coaching and the impact of Wade Phillips. This Broncos defense is not strikingly different from the 2014 personnel that Jack Del Rio had at his disposal. But Wade Phillips is so much better at schemes and tactics that this defense certainly looks like it finally could be capable of supporting Manning. Last year the Broncos played 10 teams who had winning records at the time they met. These teams averaged 24 ppg against Denver, forcing the Broncos offense to average 29 ppg to defeat them. Last year, teams scored TDs on 60% of drives which extended into the Broncos defensive red zone, and scored points on 85% of said drives. This year, those numbers have been reduced to TDs on 38% of drives (3rd best) and scores on only 50% of drives (tied with Jets for best in the NFL).

The offensive line needs time for proper cohesion. Thru the first 2 weeks, Peyton Manning was pressured on 30.4% of his dropbacks and sacked on 25% of those pressures (per Pro Football Focus). The only quarterbacks sacked at a higher rate were Drew Brees and Marcus Mariota. Sunday night vs the Lions, Manning was sacked on only 10% of the pressures (which were on 23% of his dropbacks). Both are clear improvements. The use of the pistol formation and other future influences by Peyton Manning into the Gary Kubiak offense should only help Manning's comfort and thus, efficiency in the pocket.

Despite the shaky start to the season, there are reasons to be hopeful Manning can improve his performance moving forward. A big part of that has to do with the future schedule. Remaining for the Broncos are only 6 teams who currently have winning records (Vikings, Raiders, Steelers, Packers, Patriots and Bengals), and five of those games are in Denver.

But the long term trend Peyton has experienced, in part due to age and health issues, indicates that Manning's performance inevitably will decline later in the year. Peyton has yet to play a single game in the cold, or has yet to throw a single deep pass into the wind. Watching his mechanics and effort into the passes he is attempting, including those vs the Lions, it's evident that "effortless" is far from the word to describe Manning's ability to push the ball downfield. Due to their remaining schedule as well as their defense, the impact of Manning's late-season decline will be minimized as much as possible.

But even when he should be at his best, rested & early in the season, playing in great weather conditions, the Broncos have led going into the 4th quarter this year by 3 points, 2 points and 0 points. They needed a +4 turnover margin (and 5 total takeaways) from the Chiefs to even earn that last second win by 7 points. Historically, teams who are +4 in turnovers with 5 total takeaways have won 98% of their games (by an average of 18 points) the past 15 years.

It's possible to look on the 3-0 start for the Broncos optimistically based on results, or pessimistically based on process and statistics. The latter typically is far more instructive and predictive. It will be very interesting to see the form of this Broncos' offense late in the season and into the postseason, if Manning's downward late-season trend continues, and if it costs the Broncos in their run for the ultimate prize.