HOMESTEAD, Fla. -- Brad Keselowski, loud, a little buzzed and soaked in beer, bounded through the door with an oversized bottle of champagne in one hand and his cellphone in the other.
He plopped down next to Roger Penske, a pillar of the American auto industry, and triumphantly slapped him on the back.
"We did it boss," Keselowski hailed.
"Did you bring your tweeter?" the 75-year-old Penske replied.
NASCAR's oddest couple captured its biggest prize Sunday, when Keselowski brought Penske his first Sprint Cup championship 40 years after the owner's first stock car race.
He beat five-time champion Jimmie Johnson of mighty Hendrick Motorsports while delivering the crown that fills a glaring hole on Penske's otherwise sterling racing resume.
Penske is considered the gold standard of open-wheel racing -- he has 15 Indianapolis 500 wins -- and his empire makes him one of the most successful businessmen in America.
But until Sunday at Homestead-Miami Speedway, his NASCAR program was never more than average.
"Personally, I feel amazing that I've been able to achieve this in racing," Penske said. "I think it took guts for me to stay in the sport. We could have thought, 'Well, we won the Indy 500 15 times and we're a big deal.'
"But I'll tell you one thing … I think I just woke up here tonight, and it's a big thrill."
As always, Penske credited his entire organization.
But the program really turned behind Keselowski, you know, the kid you first heard about when he tweeted from inside his car during the season-opening Daytona 500 earlier this year.
So it was fitting that his first act as champion was sending a tweet, of course, from inside his car. "We did it," he posted with a picture.
Then the party really began.
The blue collar, Twitter-loving, Michigan native chugged sponsor Miller Lite's product, donned goggles to douse the Blue Deuce crew with champagne, and imagined how his life will change as NASCAR's champion.
At 28, he's the eighth-youngest champion in NASCAR history and proud he doesn't have a date for the Nov. 30 champions banquet in Las Vegas.
"I've always wanted to date a celebrity," Keselowski said, "I'm just throwing that out there. That would be really cool, don't you think?"
Penske could only shake his head in bewilderment.
"Maybe I am conservative, but I like to have a little fun, too," Penske said. "And I think when you've won the NASCAR championship, the driver, you can kind of give him a little wider path, and he's certainly taken it side to side. I think it's all good."
Keselowski might not have seemed like Penske material three years ago, but he's a cornerstone now.
He was a developmental driver for Hendrick Motorsports in 2008 when he went to see Penske, convinced he could be the driver to bring "The Captain" a coveted Cup championship.
He wiggled free from his contract a year later, and had a second-tier Nationwide championship -- and a closet full of starched white Penske shirts -- to show for his convictions.
Now, three years into the partnership, he and Penske have that Cup championship and a connection no one saw coming.
"Always, throughout my whole life I've been told I'm not big enough, not fast enough, not strong enough and I don't have what it takes," Keselowski said from the championship stage.
"I've used that as a chip on my shoulder to carry me through my whole career. It took until this year for me to realize that that was right, man, they were right.
"I'm not big enough, fast enough, strong enough. No person is. Only a team can do that."
Keselowski needed 125 starts to win his first championship, the fewest starts since four-time champion Jeff Gordon won his first title in 93 starts in 1995.
Keselowski also won a second-tier Nationwide title in 2010, his first season with Penske and the owner's first official NASCAR championship.
Gordon, who avoided suspension this week but was fined $100,000 by NASCAR for intentionally wrecking Clint Bowyer last week at Phoenix, overcame the controversy to win the race in a 20th-anniversary celebration for sponsor Dupont and Hendrick Motorsports.
It was Gordon's first victory at Homestead, which leaves Kentucky as the only active NASCAR track where he has yet to win.