The notion of a vibrant 22-year-old with such a sunny disposition and future having enough of a professional past to grow nostalgic about anything doesn’t compute.

But Joey Logano, who one month past his 19th birthday became the youngest winner in NASCAR Sprint Cup history, will mark a milestone of mixed emotions Sunday. The Ford EcoBoost 400 at Homestead-Miami Speedway will be Logano’s final Cup race for the Joe Gibbs Racing team that brought him into major-league stock car racing.

The pole position he claimed Friday with a lap of 176.056 mph on the 1.5-mile oval is the first of a couple going-away presents he would like to present to JGR crew members and shop workers. The greater gift would be a third career victory.

For a fleeting moment anyway, Logano snatched Ford Championship Weekend’s spotlight from Brad Keselowski and Jimmie Johnson, who will determine the 2012 Cup championship in the season finale.

Keselowski, who needs only to finish 15th to secure his first championship, exceeded his own expectations when he qualified third-fastest at 175.092 mph. Johnson will take the green flag 10th, within immediate striking distance but knowing he must not only race past Keselowski but start putting distance and lots of rivals between them.

Logano, nudged from his No. 20 Home Depot ride in 2013 by Gibbs’ signing of 2003 Cup champion Matt Kenseth, will go from one high-profile team to another and become a teammate of Keselowski’s at Penske Racing next year.

He said he hadn’t dwelled on the emotions of the switch until “I went to the shop [this week] and the guys started coming up to you and shaking your hand and all, and you’re like, ‘Holy cow! This is really it.’ ”

Logano, who will share the front row with affable Australian Marcos Ambrose, would be excused for taking a rooting interest in his future teammate. But that, he assured, is incidental to his mission.

“Goal No. 1 is to win no matter what,” he said. “Obviously, I’m going to race the guys [competing] for the championship clean. I don’t want to be the guy that gets in the middle of that. But at the same time, I’m out there to win.”

He made history on June 28, 2009, when he won a rain-shortened race at Loudon, N.H., precisely one month and four days past that 19th birthday. But career victory No. 2 took until June 10 of this year at Pocono.

But, remarkably, Logano had been reaffirming the talent the Gibbs team had spotted initially with one of the most spectacular Nationwide Series seasons in memory.

Though drivers are permitted to compete for a championship in only one of NASCAR’s three primary series, Logano has dominated in his 21 “moonlighting” starts in a Gibbs Racing Toyota.

He has steered to nine victories, including in three of the past five events in the 32-race season. He will attempt to make it to double figures Saturday night in the Ford EcoBoost 300.

“One for the thumb is what we’ve been saying,” Logano said. “All those guys back at the shop — I’ve been working with them since I was 15 years old — they deserve it.”

Keselowski, who continued to repress even a hint of nerves over the championship showdown, admitted he was “pleasantly surprised” by his qualifying performance.

“I totally expected Jimmie to out-qualify us, to be quite honest,” said Keselowski, who doesn’t consider qualifying a strength.

Keselowski continued to cut up with reporters through media sessions. He clearly is enjoying the moment.

“This is supposed to be a great time, and I want to treat it like that,” he said. “I don’t want to sit here and be miserable with it. What’s the point of it? Why are you doing it if you’re not having any fun?”

Logano wants his last race for JGR to be his best.

“This sport is a roller-coaster,” he said. “It’s a very tough sport for sure.”

Rounding out the top 10 in the Ford 400 qualifying was: Carl Edwards, whose Sprint Cup championship run came up 1.3 seconds short last year; Aric Almirola; Clint Bowyer; Martin Truex Jr.; Kyle Busch; Mark Martin; and Johnson.