INDIANAPOLIS -- Peyton Manning still thinks he can be ready for the Indianapolis Colts' regular-season opener.

The rest of the preseason appears to be out.

Manning said Saturday he will use the next two weeks to get healthy from offseason neck surgery, a timeline that could put his streak of 227 consecutive starts in jeopardy.

"I certainly want to be out there, and it's hard to keep track of the hours I've spent in rehab," he said. "I was short-changed a little bit by the lockout and I'm going to need every bit of the next two weeks, and then I can give you more of an update with where I am."

The only four-time MVP in NFL history spoke at halftime of Saturday's second high school football game at Lucas Oil Stadium. The annual tripleheader is hosted by the PeyBack Foundation, Manning's charity.

He underwent neck surgery in May to repair a nerve and has been on the Colts' physically unable to perform list since the start of training camp.

While Colts coach Jim Caldwell hasn't said when Manning might return to the practice field, it's clear there are concerns within the organization.

About six hours before Manning spoke, team owner Jim Irsay used his Twitter account to acknowledge there is a possibility the Colts will start the season without their No. 1 quarterback.

"We r evaluating the QB sitch,#18 healing but we must 2 b prepared 4 early season possibility without him,defense has 2 pick it up,big time!," Irsay wrote.

Manning said he was unaware of Irsay's comments because he had been busy rehabbing. He signed a five-year, $90 million contract in July after the 4½-month lockout ended.

"Bottom line, we truly do not know when he will be ready," Colts president Bill Polian told ESPN senior NFL analyst Chris Mortensen. "Once the nerves regenerate properly, he'll be ready. When that happens, he'll be ready to ramp up immediately. It's impossible to predict."