FORT WAYNE – Youth was out the window six weeks ago for us.

– Bruce Arians, Colts

And so you forget, sometimes.

You forget that the quarterback is a rookie and a bunch of his receivers are rookies and the leading rusher is a rookie, and the leading tackler is one season removed from rookiedom.

You forget, as the quarterback uses his brains and his arm and his feet to steal one in Detroit that was all but out the door, that the Cool Hand of The Luke was a college kid just six months ago.

You forget that none of this was supposed to happen, not now, not this soon. That 8-4 seemed as likely back in August as a paper airplane landing on Mars. That, with 4-8 Tennessee on the docket for the second time this season, it’s the young Colts who have their opponent sighted in instead of the other way around.

Even Titans coach Mike Munchak recognizes this.

“They have confidence now,” he said last week. “When you’ve won eight games, and you win close games, I think you start believing that no matter what happens, you’re going to win.”

And that is to head coach Chuck Pagano’s credit and to acting head coach Bruce Arians’ credit and to the credit of Ryan Grigson and the front office, which salted the roster with young players who have resolutely refused to act their age. Andrew Luck is first among them, of course, but it’s not just about his maturity. It’s about the maturity of rookies T.Y. Hilton and Dwayne Allen and Coby Fleenor, and sixth-year pro Donnie Avery, and rookie running back Vick Ballard, and second-year man Jerrell Freeman on defense.

Freeman leads the Colts in tackles. Ballard leads the team in rushing with 468 yards. Avery has caught 49 balls for 675 yards and three scores; Hilton is averaging 15.1 yards a catch on 39 receptions, five for touchdowns; Allen averages 12.1 yards on 36 catches. All told, five rookies have at least 10 receptions so far this year.

They don’t play young. And they don’t sound young, either.

“As a locker room, we don’t buy into what people say too much,” Luck said this week. “I think we would have fun regardless of what people’s expectations are.”

“B.A. (Bruce Arians) said last week that once you get to the pro level, you are not expected to quit and I guess we just take that to a whole other level,” Ballard added. “That’s part of our job. We take it with pride.”

And, yes, maybe that doesn’t happen as quickly if Pagano had not been stricken with leukemia. As Arians notes, youth took a powder the day that happened.

“I think there are times, … we play more mature than people give us credit to be because we have so many young players,” he said this week. “But they are mature, solid players.

“I think the greatest tribute to this bunch of guys is how well the next man has stepped up. I think we’re up to 14, now, different new faces coming in, and I think we lead the league in (injured reserve) guys. (Now) there’s Jamaal Westerman going to play Sunday. He got here today, everyone learned his name and his face, and he’s willing to jump in and join hands with us. That’s the way it’s been all the way along.”

All the improbable, wondrous way along.