Peyton Manning is a legend. Unfortunately for him and the Broncos, he hasn't played like it this season. Statistically this has been one of if not the worst season in his career. He has a grand total of 9 touchdowns compared to 17 interceptions, his QBR is 67.9, almost 30 points below what it normally is for him. In wins he has only 7 touchdowns an 11 interceptions. He's completed fewer than 60% of his passes. All this despite his average pass attempt distance being fewer than in years past (6.80 this season compared to 7.67 on average.
In reality, it doesn't matter who the Broncos have as quarterback. The reason the claimed top spot in the AFC was because of their defense which is the best in the NFL. If they win the Super Bowl, it won't be because of Manning, it will be their defense that lands them the ultimate prize.
Peyton Manning is clearly one of the greatest quarterbacks of all time, but his play this season was awful. He was the worst quarterback in the NFL this year, and that's honestly not even debatable. He was dead last in quarterback rating out of the 34 qualified quarterbacks and threw an incredible amount of interceptions. The Broncos won a lot of games with him at quarterback, but it was the defense and other factors that contributed a lot more to their success than Manning. With any other quarterback, the Broncos probably would have won even more games.
Peyton Manning is still a great quarterback. The Broncos have not taken the time to prepare the team to be successful without Manning. Until they throw repetition after repetition with the new quarterback and the receivers they will never be prepared to win. Without Manning they never would have gotten as far as they did and hopefully they take what they have learned and grow from it.
Manning brought the Broncos back from the dead yesterday. The Broncos had 5 turnovers and weren't going anywhere. Manning was able to rally the team and score multiple touchdowns to win the game. It didn't look like Osweiler was going to be able to bring the team back for the win.
I don't think the Denver Broncos could have done this without Manning. The minute he (Manning) walked on the field there was a surge of energy in the entire stadium and this energy and hype carried over to each and every player giving them that winning spirit the whole game, Not to mention that Manning totally dominated every second he was on the field. He was in complete control and operated as if his injury never happened. He guided scoring drives and played a totally unselfish game which proved very effective and took his team to the win.