William Byron wins 2017 XFINITY Series championship

RELATED: Full race results | Custer wins at Miami | Sadler confronts Preece

HOMESTEAD, Fla. – William Byron drove his car directly into a special “Champion’s Victory Lane” on the Homestead-Miami Speedway’s front straightaway. From the moment he pushed the brakes to stop for the celebration to the time he accepted the trophy and made his way into the champion’s press conference, the smile never left the 19-year-old XFINITY Series champion’s face.

He probably wore a different, more serious expression only a few minutes earlier as he battled door to door, bumper to bumper with his JR Motorsports teammate Elliott Sadler for the championship, passing the veteran for third place with nine laps remaining despite a scrape with the wall.

Byron finished third in the race, behind first-time XFINITY Series winner Cole Custer and another veteran Sam Hornish Jr. But it was good enough for the title and great enough to properly send him off into the Monster Energy NASCAR Cup Series level next year where he will drive the No. 24 Chevrolet for Hendrick Motorsports.

“I don’t think I breathed the last 20 laps,” Byron said after climbing from his car. “It’s incredible. (Elliott Sadler) raced me clean, and we just raced hard for it.

“… I just have to thank this team. This is awesome … I’ve just got to thank God for giving me this platform to perform.

“I can’t believe this, ” he said, adding with a smile, “I’m tired, whew.”

His team owner, retiring Monster Energy NASCAR Cup driver — and the sport’s biggest superstar — Dale Earnhardt Jr. made his way through the crowd to the victory celebration holding his pregnant wife Amy’s hand and grinning ear to ear.

He stopped repeatedly to shake hands as he made his way to celebrate with Byron and officially hoist the hardware. It’s the second time in the last four years his JR Motorsports team has won the XFINITY Series driver championship and the drama involved Saturday evening will certainly make this one to remember.

After making it to the media center post-television interviews and official celebratory obligations, Earnhardt conceded it was absolutely an emotional final few laps.

“I don’t know if I enjoyed the last 20 laps,” he said. “I was sick to my stomach. It was hard to feel happiness and sadness at the same time. As they were changing positions it was gut-wrenching. The race was freaking great, but as they kept changing positions it was hurting my stomach.”

His sister and JR Motorsports co-owner Kelley Earnhardt Miller agreed, “My emotions were everywhere. I just didn’t want them to wreck each other.”

And, she added with a grin, “I didn’t want to have to go to Christmas luncheon after they had wrecked each other.”

RELATED: Kelley Earnhardt Miller’s reaction

As Byron conducted his interviews, his entire Charlotte, North Carolina-based family sat in the rear of the media center room, pride and happiness emanating.

“It’s just an amazing thing,” Byron’s father Bill told NBC Sports. “It’s been his passion, something he’s always wanted to do. We chose to support his passion and his dream and couldn’t be prouder of all the hard work.”

It’s a trait well recognized in their son. His former Camping World Truck Series team owner Kyle Busch praised him publicly Friday for his poise and natural talent. And Earnhardt was equally as complimentary.

“I’m happy for William,” Earnhardt said. “This kid is the total package. Obviously we see he’s got talent but what is going to be exciting … is to watch everybody else get to know what kind of person he is.

“As he gets introduced to the industry more, it will be fun to see everybody else see what we see. We never had to worry about any rookie mistakes he drove like a veteran all year. I’m thrilled for him.”