But after a 2-3 start, the Broncos have won three straight. It's an understatement to say Manning has been rounding into form. He has completed nearly 76 percent of his passes over the last five games. He leads the league in passer rating (108.6) and has 20 touchdowns and only six interceptions. He says he always expected to improve as the season wore on.
"I think you never stop learning," Manning said. "Eight games and I'm in my 15th year, you're still learning, but I think we're working to try to get on the same page and trying to be more productive each week than we were the week before."
When he chose Denver, Manning's ability to bounce back from his injury was every bit as big an unknown as how Luck would respond to his first year in the NFL. As the season has gone on and the Broncos' offense has risen to the top of the AFC West behind the league's fourth-ranked passing game, questions about Manning's arm strength have all but disappeared. The chemistry Manning built with Wayne, Marvin Harrison and Dallas Clark in Indianapolis is slowly seeping into the offense in Denver, where Eric Decker, Demaryius Thomas and Joel Dreessen are getting the hang of doing things Manning's way.
"I think the more we get on the same page, the more we understand nonverbal cues, certain routes and how to read defenses," said Decker, who has caught touchdown passes in five straight games. "All of those things, you can use to your advantage offensively. We're definitely clicking more as a unit offensively."
When Manning chose Denver, he was very clear about his goals. The decision, he said, was about winning now. At 36 and with the injury he was returning from, he knows there aren't many more seasons left to win another Super Bowl.
"I realize I don't have 14 years left, by any means," Manning said on the day he signed.
Luck, on the other hand, might. And he certainly wasn't joining a team that was one, or even two or three pieces away from Super Bowl contention.
Or so the Colts thought.
Asked to compare the quarterbacks at this stage in their careers, Arians said he'd give Luck the nod, mainly because they've asked him to do more than they asked from Manning.
"Peyton, we gave two or three plays in the huddle, he was great at that phase of it, but we didn't do the no-huddle until his second year," Arians said. "I think (Luck's) a step ahead only because of what we're asking him to do. And he's doing it with a bunch of rookies, whereas Peyton had some really good players on that team."
AP Sports Writer Michael Marot in Indianapolis contributed to this report.
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