William Byron got a phone call from team owner Rick Hendrick three weeks ago asking if he felt ready to move up into the Monster Energy NASCAR Cup Series.

This past weekend, Byron got another call from the boss, again with more good news.

“He asked me what my thoughts were about driving the No. 24,” Byron told NASCAR.com Tuesday. “I was just ecstatic, just to know that I’m going to have that number and the history there.”

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Hendrick Motorsports officials announced Tuesday evening that Byron will compete in the No. 24 Chevrolet in 2018, when he is scheduled to make his Monster Energy NASCAR Cup Series debut.

Meanwhile teammate Chase Elliott, who currently drives the No. 24, will begin competing in the No. 9.

“For Chase to be in the No. 9 is really cool,” said Byron, who currently competes in the NASCAR XFINITY Series for JR Motorsports. “I raced Chase in a Late Model race a few years back and remember how cool it was to race again him. Now we’re teammates and working side-by-side and both have those numbers that mean a lot.”

Byron was initially scheduled to take over the No. 5 Chevrolet currently driven by Kasey Kahne. That number will not be used by the organization in 2018, however.

The No. 24 has been used in NASCAR as far back as 1950, the second year of the series’ existence. But it wasn’t until the mid-90s and the arrival of a fresh-faced Jeff Gordon that the car number began turning up in Victory Lane.

For 20 of the 23 years he competed full time, Gordon parked the No. 24 in Victory Lane on what would often seem a regular basis, winning 93 races, four championships and 81 poles.

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“It’s really special for me just because of how much it means to Hendrick Motorsports and the legacy that Jeff Gordon and everybody on that team left behind,” Byron, 19, said. “It’s a really neat connection for me, something that I will take a lot of pride in running the number and hopefully be able to make my own name with it and be able to keep the legacy alive.”

Elliott ascended to the No. 24 ride when Gordon stepped aside following the 2015 season and has done remarkably well with the team, finishing 10th or better in nearly one-half his career starts. He has 16 top-five and three second-place finishes.

The No. 9, however, carries much Elliott heritage. Chase’s father, Bill, scored 38 of his 44 career wins in the No. 9, as well as the 1988 series championship.

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According to Hendrick officials, personnel will remain with their respective teams — the current No. 24 crew will remain intact but the car number will now be No. 9; likewise, those with the No. 5 currently will be fielding the No. 24 next year instead.

“It’s such an honor to take over that number,” Byron said. “It’s something I never would have imagined. It’s an honor and it’s something I really look forward to. I know there’s been a lot of success behind (it). … I was looking at Jeff’s stats and it’s incredible what he did with it.”

In a release from the team, Elliott said he “wasn’t sure if I’d ever drive the (No.) 9 again.”

“It’s a huge deal to my family and everyone back home (in Georgia),” he said, “and I hope all of our fans will be pumped to see it back on the race track. There’s a legacy attached to that number, and I want to carry it on. I think it’s awesome that Hendrick Motorsports and NAPA wanted to do this. It’s impossible not to be excited.”

Elliott won the 2014 XFINITY Series championship driving the No. 9 Chevrolet for JR Motorsports. This year, Byron has three wins and is currently second in the points standings with the No. 9 team.

Byron said the No. 9 “really started with Chase” at JRM.

“It’s been a good number for me but … it’s not a number I would want to have in the Cup Series. I think it’s always belonged to the Elliotts and it’s something that’s special to them.

“I’m really looking forward to the 24 and I think it’s a new chapter for me and something I’m really excited about.”

Hendrick Motorsports also fields the No. 48 of seven-time series champion Jimmie Johnson and the No. 88 of Dale Earnhardt Jr. Earnhardt will step down from full-time competition in the Monster Energy Series at the end of the 2017 season and will be replaced by 24-year-old Alex Bowman.

Hendrick, who formed All-Star Racing, the forerunner to Hendrick Motorsports, in 1984, knows much of the history of NASCAR and said he knows what the No. 9 has meant to the Elliott family through the years.

“They’ve contributed so much to our sport,” Hendrick said, “and I’m happy we can honor that history by bringing the number back.”

There is a stipulation, however.

“I told Chase we’d only do it if he promised to win a bunch of races, so I’m going to hold him to that,” Hendrick said.

Putting Bryon in the No. 24, he said, was more of a “fit factor.”

“And that’s what I see with William and our organization,” Hendrick said. “He reminds me a lot of Jeff at that age with regard to being a special talent and having a great head on his shoulders.

“But William is also his own person with his own career ahead of him. It’s going to be fun to watch him jump in the 24 and show what he’s capable of.”

Not running a No. 5 entry was “by far the hardest part” of the car number decision,” according to Hendrick. Geoff Bodine won the organization’s first race in the No. 5 in ’84 and Terry Labonte won a championship with the car number in 1996.

“The memories and the history will always be there,” he said, “and I won’t rule out bringing it back some day. Never say never.”