INDIANAPOLIS -- Now Peyton Manning can start fine-tuning the mechanics, timing and rhythm.

Just don't expect him to try it in Thursday night's preseason game against the Cincinnati Bengals.

Coach Tony Dungy increased the two-time league MVP's workload Wednesday, one day after he finally returned to practice and showed no lingering effects from the knee surgery that kept him out for the past six weeks.

"We didn't have him in team work (Tuesday), but he did fine and hasn't experienced any problems," Dungy said. "So far, so good. He'll get a little more work today."

Manning, who has never missed a start in his 10-season NFL career, had surgery on July 14 to remove an infected bursa sac from his left knee.

Team officials initially said their franchise quarterback would miss four to six weeks, and all along Dungy, team president Bill Polian and others contended Manning was on schedule amid speculation he might miss more time. That didn't end the questions about Manning being hurt worse than first feared, nor did it end the speculation about whether he would keep his streak of 160 consecutive starts intact Sept. 7 against the Chicago Bears.

Things changed Tuesday when Manning returned to practice one day after the six-week anniversary of surgery. Indy did not practice on Monday.

Manning threw passes with velocity and moved around well Tuesday, but as with most injured players, the real test came Wednesday morning when Manning returned to the team complex.

The result: No soreness, which prompted Dungy to gradually increase Manning's workload.

"We've been telling you guys that he's been doing a lot of things, and we have a pretty extensive workout before we let guys get back on the field," Dungy said. "They go through a routine on the side and do some individual work, and it's like a decathlon. So when we clear guys to come back, I usually don't worry about how they're going to be."

Manning, like most of the team's starters, will not play Thursday even though the Colts' quarterback situation is precariously thin.

Longtime backup Jim Sorgi missed another practice on Wednesday, although Dungy said the swelling in his knee has started to subside.

Without Manning and Sorgi, the Colts have only two other quarterbacks -- veterans Jared Lorenzen and Quinn Gray, who were signed last month and are fighting for the No. 3 job. The Colts have traditionally kept only two quarterbacks because of Manning's durability. He's missed only one play in 10 NFL seasons because of injury.

But the uncertain status of Manning and Sorgi for the season opener may force Indy to rethink its philosophy when making final cuts this weekend.

"It's still to be determined from what we do, and a lot of that will be based on the medical report on Jim and Peyton," Dungy said. "So those guys (Gray and Lorenzen) are both going to play, we'll see how they do and then we'll determine whether we keep four, three or two."

Cincinnati also will be without its most prominent players, Carson Palmer and Chad Johnson, the quarterback-receiver combination that wanted to pattern their games after Manning and Marvin Harrison.

Palmer is out with a broken nose and is expected to be replaced by backup Ryan Fitzpatrick. Johnson will miss the game with an injured left shoulder.

Coach Marvin Lewis still hopes to see running back Rudi Johnson and receiver T.J. Houshmandzadeh make their first appearances of the preseason, although they will likely be in cameo roles.

"I would assume very little," Houshmandzadeh said when asked how much he'll play. "But, hey, you know what they say when you assume."

To Rudi Johnson, there's no significance to Thursday's game given the recent trade rumors.

"The (trade) situation has already been presented, the game doesn't really matter," he said.

With Manning back on the field, the Colts' biggest question mark is starting center Jeff Saturday.

Dungy has not said how much time Saturday, a three-time Pro Bowler who injured a ligament in his right knee during Sunday night's loss to Buffalo, would miss. He was at the team complex Wednesday but was not on the practice field.

"I know Jeff was visiting, getting more looks at it," Dungy said. "But I don't have an update on that."

As for Manning, who didn't speak with reporters on Wednesday, teammates thought he looked like his old self.

"It was good to see him back on the field, dressed and ready to go," right tackle Ryan Diem said. "Hopefully, he'll be back all next week. I think he'll be fine because we know how hard he works."

Copyright 2008 by The Associated Press