Indianapolis — Peyton Manning insists nothing is wrong with his game.

His confidence remains high, he's still capable of running the Colts' precision offense to perfection and, at age 34, there's no indication his skills are slipping.

Still, something is not right with the four-time league MVP.

He threw nine interceptions and was sacked eight times in November, arguably the worst month since his rookie season, and now takes a 6-5 record into a December that likely will determine Indy's playoff fate.

These are unusual times for Manning and the Colts, who play host to Dallas on Sunday.

"We're 6-5, you can argue that that is different," Manning said. "Out of sorts? No. Not confident? No. I would not agree with that. I feel that I need to play better for us to have a chance offensively to score more points and win. I need to protect the ball better. I need to find a way to convert third downs and keep us on the field."

Clearly, the problems are not all Manning's fault.

He lost All-Pro tight end Dallas Clark with a season-ending wrist injury Oct. 17. Two-time 1,000-yard rusher Joseph Addai hasn't played since Oct. 17 because of a nerve injury in his left shoulder. Receiver Austin Collie has played only three quarters in the last five games because of a thumb injury and a concussion, and blocking tight end Brody Eldridge has been limited to action in only two of the last four games with a rib injury.

But injuries aren't the only concern.

The struggles have made one of the league's elite quarterbacks look ordinary. On Sunday night, Manning threw four interceptions for the first time in his career and the first was a ball Manning later acknowledged he should not have tried to force between three Chargers defenders. Linebacker Kevin Burnett made an acrobatic catch and sprinted 29 yards for a touchdown.

Next question: Is Manning trying to do too much?

"It happens from time-to-time, I think that's human nature," Pro Bowl defensive end Dwight Freeney said. "I think everybody probably tries to make some plays because you're looking for a spark. You know, it's not going to be a perfect game all the time."

But that's not what people expect from the quarterback once dubbed Perfect Peyton.

Over his career, Manning has been the model of consistency. He's the only quarterback to open his career with 203 consecutive starts. He's been selected to 10 Pro Bowls, and he needs three more TD passes to extend his league record of consecutive 25-TD pass seasons to 13. Nobody else has more than five.

So what's gone wrong lately? Almost everything.

The loss of Addai cost Manning his best blitz protector, an outlet receiver and Indy's top runner.

Without Addai, Manning simply hasn't been the same. Manning threw 48 times Sunday while the Colts ran 13 times for 24 yards, and in the five November games — all without Addai — Indy ran 102 times for 340 yards and three scores.

That's not good enough to keep defenses off balance, and has forced Manning to shoulder more of a burden.

"I think we're throwing the ball a lot. Somebody said we're on pace for 600-plus attempts. That's more than anybody would have said (we) would like to throw this year in the passing game. That's more than I would like to throw," he said. "We still want to be what I've always called a three-dimensional offense: first-and-10, drop back; first-and-10, handoff; first-and-10, play-action pass. When you have to throw that much that means you probably aren't three-dimensional like you want to be."

The difference is obvious.

Though Manning had been sacked just five times in the first six games, he's been sacked eight times since Addai went down. The Colts have tried to adapt to the poor pass protection by using shorter, quicker passes.

The result: Manning is averaging 6.88 yards per attempt — one yard shorter than last season and his lowest since total since 1998 when the rookie averaged 6.5 yards.

Defenses have adjusted, too. They're blitzing less and dropping more players into coverage, putting Manning in the unenviable position of sometimes throwing into coverage.

Manning's teammates don't blame him.

"What we have to do is win. We're just not used to losing," receiver Pierre Garcon said. "Things aren't going the way we want, and it's actually more about doing less — not making it as complicated."

But if the Colts hope to make the playoffs for a ninth consecutive year, they need Manning to play like his old traits — consistency, efficiency and productivity.

And nobody knows that better than Manning.

"I don't feel that's necessarily been a problem for anybody here," Manning said when asked whether players were pressing to do too much. "I think we just need to execute better. That's your simple solution."