"He's got great command of the huddle. That's his huddle," said guard Joe Reitz. "He's the commander and we are the troops."
Among the specific areas Luck continues to focus on include ball control, converting third downs and building chemistry with a new receiving corps.
"It's just not taking a dip or a lull practice-wise," Luck said of gauging his progress. "If you can put the film on and say, 'Okay, I made mistakes, but I didn't make the same mistakes I did the day before'. Not repeating mistakes really is what I'm trying to say."
Mathis, who is making the conversion from defensive end in the new 3-4 scheme, deemed Sunday's game a "stepping stone" for the retooled Colts.
It also means live game action at his new position, and a chance to hit opponents.
"To actually hit somebody else besides your own teammates, and to just get the frustrations out and to be able to take somebody to the ground a little bit, it's just a welcome change," Mathis said.
It's a new era for the Colts, which appears to have rejuvenated veterans like Mathis.
"Build a monster, that's what we're doing," he said. "So let's go."