ANDERSON – New Indianapolis general manager Ryan Grigson concedes he has more than a few butterflies as the Colts wrap up preparations for their preseason opener with the St. Louis Rams.

Grigson, who has spent the last nine years serving in a variety of front-office and scouting positions with the Philadelphia Eagles, will be watching his own team take the field for the first time Sunday at Lucas Oil Stadium.

Hired as the Colts’ general manager Jan. 11, replacing Bill and Chris Polian, Grigson is one of several new faces in the team’s front office and coaching staff.

“It’s excitement. There’s always the fear of the unknown, so to speak,” he said Friday.

“I have butterflies. I’m not going to lie. We’ve come such a long way in this whole process. To actually see the product on the field against another team, a different color jersey, is exciting. I can’t fake that.”

There’s been a near complete culture change in Indianapolis since Grigson took over the reins of the franchise seven months ago.

Longtime veterans, such as quarterback Peyton Manning and tight end Dallas Clark, have moved on.

And Indianapolis selected former Stanford quarterback Andrew Luck with the first pick in last April’s draft.

That wasn’t the only change. There are about 50 players on the Colts’ training camp roster who weren’t with the team at the end of the 2011 season.

“I’m not really following anybody’s template. I’m really just kind of keeping it simple. I will always explore anything that makes us better,” Grigson said. “And I think my actions speak to that. We need to keep doing that.”

Indianapolis’ first-team offense is tentatively scheduled to be on the field for 20 to 25 plays Sunday, although that could change.