INDIANAPOLIS (AP) - Indianapolis is going to protect Andrew Luck at all costs.

Even if that means shaking things up this season.

After watching their new franchise quarterback hit the ground far too often in Sunday's loss at Chicago, general manager Ryan Grigson and coach Chuck Pagano wasted no time in sending a message to the Colts' offensive line: Things must improve.

Every play matters,'' right guard Mike McGlynn said Wednesday.You can't have four guys playing and one guy messing up. You have to have five playing together.''

Sure, there are explanations for last weekend's rocky start.

The Colts (0-1) are learning a new offense, have a new quarterback and center calling plays, and Sunday's game marked the first time that the starting five - Anthony Castonzo, Seth Olsen, Samson Satele, McGlynn and Winston Justice - played together extensively on game day.

Still, allowing three sacks, a rash of other hits on Luck and rushing for only 63 yards simply wasn't good enough. And an encore certainly won't get the job done this week when Minnesota (1-0) comes to town with Jared Allen, the league's reigning sacks champ, and a defense that produced a league-high 50 sacks in 2011.

The first game was a big, big experience for us, and a lot of guys can learn from it,'' said Satele, whose 75 career starts are more than Sunday's other four starters had combined (66).It will be a lot different this week.''

Grigson and Pagano expect things to go more smoothly this weekend at home.

The linemen have a better idea of one another's strengths and weaknesses and can scour game tape to make corrections.

They'll also being playing in a friendlier, quieter environment that should allow them to hear audibles more clearly and perhaps get off the ball a split-second faster, key ingredients to protecting Luck.

But there are bigger problems, and Grigson again is trying to fix those by tinkering with the roster.

On Monday, he waived tackle Mike Person and center A.Q. Shipley and brought in former Steelers guard Trai Essex. On Tuesday, Indy signed 320-pound rookie tackle Bradley Sowell from Tampa Bay's practice squad and re-signed Shipley to the practice squad.

Essex could plug a major need as soon as this weekend.

He spent the last seven years in Pittsburgh, the last five working with offensive coordinator Bruce Arians. The Steelers cut Essex during the final cutdown. Arians is running a similar offense in Indy, so Essex knows it better than almost anyone on the Colts' roster.

This is my first day of practice so we'll see what he (offensive line coach Harold Goodwin) has for me right now,'' Essex said.It's an offense that I'm familiar with obviously. It's still a different system, a different program.''

Essex, like defensive end Cory Redding, will serve as a mentor by helping his new teammates learn the system.

If the Colts are going to keep the top draft pick upright another 15 games, they're going to need to stay healthy, too.

Pagano said this week that left guard Joe Reitz will miss another week with an undisclosed knee injury. Reitz did not practice Wednesday.

It's also unclear if starting right tackle Justice will play after being diagnosed with a concussion in the season opener. Justice was limited in practice Wednesday.

Whatever moves the Colts make, there's one common denominator - Indianapolis will invest whatever it takes along the offensive line to protect their biggest investment this season, Luck.

We've talked about it at length. It seems to keep coming up about the offensive line,'' Pagano said.There are a bunch of new guys in there. They are learning the new system. We make no excuses. They'd be the first to tell you that they're going to play better. They want to play better.''

NOTES: Outside linebacker Dwight Freeney is listed as day-to-day with a sprained left ankle and was held out of Wednesday afternoon's practice. ... Pagano said receiver Austin Collie (concussion) has been cleared to practice and play this week and that receiver T.Y. Hilton (shoulder) should play Sunday. Both were full participants at practice Wednesday. ... To make room for Shipley on the practice squad, Indy released receiver Kashif Moore.

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