There might not be a team in sports more reliant on a single player than the Indianapolis Colts are on Peyton Manning. That’s why the eyes of the football world are trained on Manning’s neck, which had part of a bulging disc surgically removed on May 23.

That was 96 days ago, and although it was supposedly a “minimally invasive” procedure, we haven’t seen No. 18 throw a football since. It’s easy to forget that the seemingly immortal Manning is human, but he’s 35 now, and he’s undergone two neck surgeries in just over a year.

It’s all taking its toll on the NFL’s active iron man.

And it’s taking its toll on the team, which earlier this week was forced to usher 38-year-old Kerry Collins out of retirement to provide Manning insurance. And although Collins is an upgrade over Curtis Painter, he’s not Manning. No one is. There isn’t a quarterback who can reasonably learn the nuances of the Colts’ extremely unique offense and put it into action (successfully) in less than three weeks.

And if the Colts are already preparing for life without Manning now, if they’re already starting to question whether he’ll be ready for Week 1 with 16 full days before the opener, that has me wondering if the four-time MVP could be in jeopardy of missing more than just a single game. Even the Colts can survive for a week or two without their franchise leader, but beyond that? Indy has Pittsburgh in Week 3 and a talented Bucs team in Tampa in Week 4. The Chiefs, Saints and Falcons linger in the weeks that follow. They don’t get an off week until the middle of November.

Without Manning close to 100 percent, they won’t survive the first half of the season.

And I realize that the guy is a warrior. I realize that his former coach said he’d be on the field Sept. 11 “unless he’s dead.” But this isn’t the kind of injury you can shake off. The neck, I’m told, is sort of important, especially for a quarterback who has to work both sides of the field prior to the snap and as the play unfolds.

The Colts haven’t missed the playoffs since 2001, a remarkable feat in a league draped in parity. They’ve dominated the AFC South since its inception in 2002. They’ve consistently been one of the best teams in football for a decade.

But there’s a chance the run is over.

2010 in a nutshell: Injuries to key contributors such as Dallas Clark, Melvin Bullitt, Jerraud Powers, Anthony Gonzalez and Austin Collie make it impossible to dominate, and they once again have trouble running the ball and stopping the run. But Manning and his offense find a way to get them into the playoffs at 10-6. They lose to the Jets on wild-card weekend.

Three predictions for 2011:

1. Manning will play at least 13 games: Hey, I only said there’s a chance the run is over. I still have faith in Manning, and I believe the team does too. They wouldn’t have given him a five-year, $90-million contract earlier this month if doctors didn’t think he could rebound from this injury. I don’t think he’ll start the season, but I do think the Colts will survive two or three weeks with Collins and/or Painter before battling back with No. 18 in the lineup. And if you’re worried about Manning’s ability to stay healthy once he returns, consider that he surrendered just 16 sacks last year despite playing behind a crappy offensive line.

2. Delone Carter will help a bad running game: Technically, the running game improved last year after putting up embarrassing numbers in 2009. But 3.8 yards per carry still isn’t enough support for Manning and a group of injury-prone and/or aging receivers. In a new attempt to keep defenses honest, they spent a fourth-round pick on an ideal change-of-pace, short-yardage back, Syracuse’s Delone Carter. Expect Carter to emerge as a go-to red-zone back and score a lot of touchdowns. He, Donald Brown and a healthy Joseph Addai could be a respectable trio. Now, if they only had some help from those mediocre/unproven guards and tackles…

3. The front seven will provide more support for a good secondary: After struggling to register sacks and stop the run last season, the team addressed the front seven by adding a few veterans to the fray. Expect Jamaal Anderson, Tommie Harris and Ernie Sims to play big roles. If Dwight Freeney and Robert Mathis can get help from that trio and 2010 first-round pick Jerry Hughes can contribute in any way, they’ll be much better up front. With Bullitt and Powers back, the defensive backfield is in solid shape, but they aren’t deep, so they’d better stay healthy this time.

The final word(s): It would be great to see the Colts host the Super Bowl in Indy in February, but I just can’t see them keeping up with the Steelers and Patriots in the AFC. In fact, they’ll have their hands full in their own division for a change. I think the playoff streak continues, but they’ll finally surrender the AFC South to the Texans.