Manning's arrival in 1998 heralded a fresh start for a franchise that had not visited a Super Bowl in more than 20 years and was rumored to be on the road to Los Angeles or Cleveland.
Outside Lucas Oil Stadium, fans shot photos of the quarterback on the giant banner that hangs off the side of a complex some call "The House That Manning Built."
"I think the Colts need to right now affirm to fans that this is our brand, this is what we stand for," said Compton. "Back in 1998, people kept telling me this is not a football community, this is not a football state. I think for the last 15 years it has been and now the question is: What is the next step?"
It's assumed Manning's position will be taken by Andrew Luck, the Stanford quarterback expected to be the Colts' number 1 draft pick next month. Kim Donahue, marketing lecturer at IUPUI, said it would be a mistake to make Luck the centerpiece of any new Colts image plan.
"And now the Colts have to be in a position to jump into a void and say, 'We're not the same Colts we were before but here's where we are going forward,' and that's a tall order."
Donahue said the Colts ought to emphasize their returning veteran players while promising a brighter future ahead.
"When we look at Peyton leaving, we're looking at it from a business decision. We're also looking at it from the community but we're also losing part of our family.
"He is ours. He belongs to us and now that he's leaving we're going to experience an empty nest syndrome," said Donahue.
Compton said while Maning was undoubtedly the on-field leader of the franchise, the heart and soul of the Colts belong to the team's owner.
"I think Jim Irsay is the culture of this franchise, even more so than Peyton to some degree and I think Jim Irsay is committed to this process," said Compton. "The roots are in the soil and this city has roots now when it comes to the Colts."