Freeney and Bob Sanders sat out the team’s three-week stay in Terre Haute, Ind., before returning to practice. Freeney had season-ending foot surgery in November, and Sanders, last year’s NFL defensive player of the year, had offseason shoulder surgery.

Harrison, who missed most of last year with a left knee injury and had offseason surgery on his right knee, has looked like himself as he nears his 36th birthday.

But coach Tony Dungy also has 10 of 11 defensive starters back from a unit that allowed the NFL’s fewest points (262). Only outside linebacker Tyjuan Hagler, who tore a pectoral muscle while lifting weights in the offseason, is not expected to start on opening day. He could be out until October.

The continuity, coupled with Manning’s injury, has raised the stakes for the defense.

“We had some success last season and our goal is to get even better,” Brackett said. “When you look at the tape, there are a lot of things we could have cleaned up last year.”

Whoever starts at quarterback against the Bears will still have an array of options.

Reggie Wayne wants to improve on his career-high 104 receptions and league-high 1,510 yards from last season, and Harrison hopes to return to the record-setting form that sent him to eight consecutive Pro Bowls. Also back are tight end Dallas Clark and four of last year’s starting linemen, although left guard Ryan Lilja remains on the physically unable to perform list.

Joseph Addai played in his first Pro Bowl in February. The Colts also added depth at running back, bringing back Dominic Rhodes, who teamed with Addai for the Super Bowl run.

So Dungy believes the offense should be just as efficient — with or without Manning.

“Everybody can say, ’Oh, if Peyton Manning isn’t playing, the Colts are going to be a .500 team,”’ Dungy said. “I don’t think anybody here believes that. Is it easier to win without Peyton? No. It’s going to be tougher.”

Meaning the questions surrounding Manning loom even larger if the Colts plan on returning to the Super Bowl.

“Certainly, all along, that has been our goal, to try and get back onto the field in order to play the first game,” Manning said. “It just depends on how everything goes from here on out. Obviously, the sooner, the better for me.”

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