At 20, and in the No. 24 car, William Byron (and the hype) is here

William Byron won the Xfinity Cup even after his 2018 ride on the Sprint circuit was assured. AP Photo/Ralph Freso

The meteoric rise of William Byron, who first drove a race car in 2013 and has since become the Xfinity Series champion in 2017, continues to amaze.

Byron's composure and natural talent throughout the past two years have guided him to the point where he will drive the famed No. 24 next season at Hendrick Motorsports. The No. 24 car ... and he's still just 20.

Byron won seven Camping World Truck Series races in 2016, only to get booted from the playoffs thanks to an engine failure late in the race at Phoenix, where he had dominated and appeared as the championship favorite.

By that time, he already knew he would leave Kyle Busch Motorsports for JR Motorsports as a Hendrick Motorsports developmental driver. At a news conference following his signing with Hendrick, he remained composed as questions about the future and him potentially replacing either Kasey Kahne, Dale Earnhardt Jr. or Jimmie Johnson where tossed around.

It turns out those questions were warranted. In August, as Kahne continued to struggle, Byron was named as his replacement for 2018. Of course Byron still had an Xfinity season to finish, and he did so in grand fashion. His third-place finish at Homestead-Miami Speedway vaulted him to the championship in a year in which he posted four wins, 12 top-5s and 22 top-10s as a rookie.

In the finale, he passed Elliott Sadler late in the race and held on for the top spot among the four championship finalists. He will enjoy and relive his title Saturday at the annual awards ceremony that combines the season-ending celebrations for the Xfinity Series and Camping World Truck Series.

"Some guys just have it," said Earnhardt, a winner of two Daytona 500s. "Some people just have it in them.

"He shouldn't be able to do what he did [at Homestead] at his age with the limited experience he has, but he has it. He just has whatever it is about his mental toughness, and his ability to remain calm in a very high-pressure situation is going to serve him well in this job for sure."

Earnhardt said understanding what a driver needs to be fast is something that Byron learned in the trucks at KBM.

"He's just getting started," Earnhardt said. "It's going to be impressive to watch him as he really starts to get more and more confidence in himself and people around him."

Winning the championship had no impact, theoretically, on Byron's future. After all, his Cup ride had been assured months earlier. But it could have an impact in how he performs.

A driver gets behind the wheel at Hendrick Motorsports with the expectations of competing for a title. Byron has won one.

"We've grinded out the last couple weeks, whether it's in the simulator or just some conversations and just figuring out what it is that we really needed," Byron said following the championship race.

"What it did most for me is like what Dale said, I had a chance to go to Kyle's and figure out what it's like to drive the competition in that series -- the trucks they have, it's incredible. To come here, and there's a lot more competition and you have to know what you want to feel in the race car and the races are longer, it helped me understand how to get from point A to point B and in the race how I want to be."

The jump to Cup will be bigger than anything Byron has experienced. It challenges even the best. Kyle Busch finished 20th in the standings in his Cup rookie year.

"I appreciate William's efforts," Earnhardt said. "[He] came in as a rookie. We never had to worry about any rookie mistakes.

"He's drove like a veteran all year, and thrilled for him to be able to take this [Xfinity] trophy and put it into his resume as he moves on up into the Cup series next year."

Byron drove a late model at JR Motorsports before driving for Busch and then returning to JRM for the one Xfinity season.

"He's the total package," Earnhardt said. "Obviously, we see he's got talent, but I think what is going to be exciting for ... everybody that already knows him so well, is to watch everybody else get to know what kind of person he is.

"As he goes on to the Cup series and he gets introduced to the fans and the industry more, it's going to be fun to hear everybody else see what we already see."