The enormous banners of Manning that had loomed from the side of Lucas Oil Stadium were removed long ago, in the days just before the Colts selected Luck in April. But inside the building, the win over the Packers was the moment that Luck’s unobtrusive arrival was complete. Luck has purposefully chosen to be low-key in his entrance to the N.F.L., and if a first overall draft pick can fly under the radar, he has managed to do it.

He has filmed a commercial for a soccer video game, but that is about it for high-profile endorsements. That is in part because Luck’s aw-shucks personality does not mesh well with the limelight. But it is also because Luck’s father, Oliver, a former N.F.L. quarterback who is now West Virginia’s athletic director, has encouraged his son to keep his life simple for the first couple of years as a professional, the better to focus his attention on the field. Luck is able to go to dinner with teammates near his downtown Indianapolis home and dine relatively undisturbed.

But the Colts are 2-2 — already equaling their victory total from 2011 — and Griffin’s style of play has been questioned since he sustained a concussion while scrambling in the Redskins’ loss to Atlanta on Sunday. Luck’s performance against the Packers seemed to remind the league this week, as the Colts prepared to play the Jets, why Indianapolis chose to rebuild around him.

Gil Brandt, a former Dallas Cowboys personnel executive who continues to scout college players for NFL.com, said Luck’s second half against Green Bay might be the best performance by a rookie he had ever seen.

None of this is likely to move the needle on Luck’s demeanor. He is famously cerebral and less-famously composed and self-deprecating. Colts center Mike McGlynn described him as “egoless.”

Christensen said Luck wanted to be a normal guy. Luck’s first major piece of new furniture after he signed with Indianapolis was a Ping-Pong table that he claimed was deluxe. Christensen invited Luck to his home to play and asked Luck to give him odds that the coach could beat the quarterback. Luck told Christensen the odds were 8-1. Christensen won, and Luck left dejected.

“Typical N.F.L. quarterback,” Christensen said. “He wanted to bring his own paddle next time.”

But everyone around Luck struggles to think of a moment when he has seemed overwhelmed this year. Oliver Luck said that his son had never been one to cause much drama and that even if he had doubts or concerns, he would probably keep them to himself. Andrew Luck paused for several long beats trying to think about something that surprised him about the N.F.L. before marveling at how big a machine the league is and how many people — from coaches to public relations staff members — work so many hours to keep it moving.