ANDERSON, Ind. (AP) - Indianapolis' rebuilt offensive line understands the assignment.

It must protect the new franchise quarterback from oncoming pass rushers and confounding blitzes, keeping Andrew Luck upright long enough to stay healthy.

While some contend it's an impossible mission for a unit with so many new faces, the Colts insist it can be done without self-destructing.

We've got to earn respect. We know that,'' new center Samson Satele said.We all know that nobody is going to say we are a dominant offensive line until they see it.''

Or at least until they see all these new guys working in unison for the first time.

In the seven months since fans last saw the Colts walk off the field in Jacksonville after securing the top pick in the draft, everything has changed.

Longtime Pro Bowl center Jeff Saturday left for Green Bay in free agency. Longtime right tackle Ryan Diem retired after struggling at guard last season. Last year's starting right tackle, Jeff Linkenbach, has moved inside and is now battling with the incumbent, Joe Reitz, to start at left guard.

And that's just the start.

Under former Colts executive Bill Polian, the Colts relied on smaller, more athletic players to protect Peyton Manning, rather than the mammoth-sized men other teams coveted. It worked for more than a decade, as the Colts remained a perennial Super Bowl contender despite ranking near the bottom of the league in rushing each of the past three seasons.

New general manager Ryan Grigson and new coach Chuck Pagano have a more conventional philosophy. They've added size to the line in hopes of bringing balance back to the Colts' offense - a move that could help keep pass rushers off Luck, Manning's replacement.

We're putting more emphasis on finishing and nastiness and playing with an edge,'' Grigson said.I think the guys have that and that's the way the game has to be played.''

Grigson wasted no time in shaking up things.

First, he sent a sixth-round draft pick to Philadelphia for Winston Justice, the 6-foot-6, 317-pound tackle taken in the second round of the 2006 draft when Grigson was scouting for the Eagles. Then, Grigson signed 327-pound guard Mike McGlynn, who spent his first three NFL seasons with the Eagles before moving to Cincinnati last year.

Both are expected to start.

Grigson's next move was signing Satele, a free agent who had 74 career starts in Miami and Oakland. By giving Satele a three-year, $10.8 million deal, the Colts made it clear the 299-pound center would anchor the line and develop the kind of close relationship Saturday had with Manning.

It's already starting to look a little Manningesque.

Samson is an all-star,'' Pagano said.He's a really bright guy. He's played. He's a veteran, a very selfless guy. When I asked him, `Hey look, Andrew wants the locker next to you, do you mind moving your locker?' he picked up his stuff and he moved his stuff over there.''

The March flurry left Indy (No. 32 in the AP Pro32) with only three returning starters from a team that went 2-14: 2011 first-round pick Anthony Castonzo, the left tackle, and Linkenbach and Reitz, undrafted free agents who fought their way into the NFL.

Castonzo had a solid rookie season, though his learning curve was impeded by the lockout and a sprained ankle that forced him to miss four games.

With a full offseason of work, Castonzo said he feels better about himself and his teammates.

Chemistry has been developing really well even before camp, and now during camp,'' he said.Our communication is getting much better. We haven't been making very many mental mistakes at all. We are coming together as a group.''

That process was complicated last week by Ben Ijalana's season-ending ACL injury. Indy's second-round pick last year missed the final 12 games with a torn ACL in his left knee and reinjured the same knee on the first day of training camp.

It doesn't help that time is running short.

Indy hosts St. Louis in its preseason opener Sunday, and visits Chicago on Sept. 9 in the regular-season opener. The Bears have traditionally had one of the league's best and most aggressive defenses, and will likely throw everything they can at the rookie quarterback.

Will the offensive line hold up? The Colts say it's not just possible, it's a mission that must be completed.

I'm a former offensive lineman, so my heart goes to that area of the team,'' Grigson said.I've seen flashes there, and I think we've got five guys who can get the job done.''

Notes: Offensive coordinator Bruce Arians said receiver Donnie Avery would probably not play in Sunday's game. Avery was diagnosed with a bruised left thigh after he made a twisting catch Sunday. ... Luck was 15 of 29 with three touchdowns and one interception Monday.

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