AVONDALE, Ariz. – Jason Ratcliff was in the middle of a radio interview when the approaching milestone came to light. His Joe Gibbs Racing No. 19 team was still fresh in celebration mode from Ty Gibbs’ Xfinity Series victory at Indianapolis Motor Speedway’s road course when the radio host brought up his veteran presence in the sport. His statistician had told him that Ratcliff’s number of starts as a crew chief in NASCAR’s national series stood at 790.

“I paused for a second. I’m like … ‘What? Are you serious?'” Ratcliff recalls. “He’s like, ‘yeah, my guy’s on it. He called out the numbers on it.’ That’s crazy.”

Ratcliff marveled then and still marvels at the ride he’s had in stock-car racing and the two decades-plus he’s spent as a NASCAR crew chief. Along the way, his journey has soaked in 72 victories – 15 in Cup and 57 in Xfinity – and the 2009 Xfinity championship with Kyle Busch.

Ratcliff reached the 800-start plateau last weekend at Martinsville Speedway. Saturday’s Xfinity Series season finale at Phoenix Raceway (7 p.m. ET, USA, MRN, SiriusXM NASCAR Radio, NBC Sports App) will mark another milestone with what’s planned to be his final appearance atop the pit box, calling the shots for Myatt Snider in the No. 19 Toyota. After the season, the 55-year-old veteran will transition to a new role as the team/driver coordinator for the organization’s Xfinity and ARCA Menards Series programs.

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Ratcliff said he took a playful jab from fellow JGR crew chief Adam Stevens heading into Saturday’s year-ending race. “801? Was that your target going in?” Ratcliff recalls him saying with a laugh, his final number akin to filling up at the gas pump and trying to stop at an even dollar amount but then blipping over by a penny. Round number or not, he says the longevity and success is more than he could have imagined from the outset.

“It’s crazy to even think about that,” he says. “It’s very humbling just to think of, you know, all the drivers and people and the race teams and to watch the sport change as much as it has over the last 20 years.”

Jason Ratcliff’s pathway into racing started early. His father, George, was a non-denominational minister who made extra money buying and selling cars. “So I was kind of his mechanic,” Ratcliff says. “Even at 10 years old, while changing water pumps and belts, I just enjoyed it.” His early automotive interests grew to include hot-rodding and helping at grassroots short tracks. When his father’s ministry work prompted the family to move periodically, Ratcliff sought out the local racing community at stops in Louisiana and Texas.

As he graduated from working with sprint-car teams, Ratcliff aspired to a full-time career in racing. One of his first big breaks came with Sadler Brothers Racing, and he also found a home with Brewco Motorsports, where he made his first appearance as an Xfinity Series crew chief in 2000.

Victories came early with a young Jamie McMurray and former series champ David Green before he landed with Joe Gibbs Racing in 2005. He’s been there ever since, and the list of drivers he’s worked with is a cast of living legends – Matt Kenseth, Kyle Busch, Joey Logano, Tony Stewart, Denny Hamlin and recently with current Cup Series title contender Christopher Bell among them.

“In the midst of it, you don’t think about it,” Ratcliff says. “When you look back at it, obviously Matt has already been inducted into the Hall of Fame, and I know there’s at least three or four others that are going to be there. So for me, 10 years from now, when I’m able to look back at that and say, wow, to work with four or five, possibly six of the guys who are in the Hall of Fame, it’s amazing.”

Ratcliff’s impact has spanned not just a select group of drivers, but he has also influenced crew members and fellow crew chiefs alike.

“He is just such a special guy,” Stevens said. “He and Dave (Rogers, former JGR crew chief), especially Jason, taught me how to do this job. Working with Jason down the street in the Xfinity shop and just seeing the way he operates, how he runs his team, how much he puts into it and what he expects out of his guys and out of his equipment, it’s pretty awesome. He’s a very special person, the hardest-working guy you’ll ever want to meet. It’s going to be a huge loss to have him not up on top of the box. … It would be really bad if he just rode off into the sunset, I think, just because he’s just got so much knowledge and he’s so good with the cars and good with people.”

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Instead of fully sunsetting his career, Ratcliff says he’s looking forward to his next chapter and the opportunity to mentor and refine JGR’s operations in its development series programs. Even as he wraps up his final season as a crew chief – one that’s produced three wins – he says he’s already assembled a substantial to-do list for his next endeavor.

“I think as a crew chief, there are many times where it’s like, ‘Oh, man, it’s in the 12th hour, I wish I had someone that can help me with X,’ or ‘I think we could be a better race team or a better organization if we just had one more person in this spot to get help with this.’ Everyone’s just sometimes spread thin,” Ratcliff says. “We can say that a lot, and a lot of times, we just want to throw people at problems and try to fix them, and that’s not the solution, but I think this role that I’m going into has been needed, and I hope I can bring value across the board to the Xfinity and ARCA program. … Most of it is just things that as I crew-chiefed over the years that I think would have been beneficial for myself and my race team. I’ll start there, and then I’ll just let it grow and learn.”

Said Bell, who spent three seasons with Ratcliff – two in Xfinity and one in Cup: “He’s one of the best ever to do it. Having him around is going to be very critical. Anyone who is young and in the crew chief role would be wise to speak to him.”

Ratcliff’s new role will keep his hand in JGR’s trajectory, but he says he’s also hopeful to have an opportunity to take a breath and reflect on what his years in the sport have meant. He says he’ll likely have a better cumulative assessment of that journey by the time the holidays roll around – “when I’m actually sitting down, not thinking about the next race.”

But Ratcliff says he’s also looking forward to taking part in those reflective moments with family and enjoying the opportunity to have an occasional vacation that’s not squeezed into the range of an off-weekend on the racing calendar. A nostalgic trip to the Amalfi Coast of Italy? Potentially documenting his ride in NASCAR in a book? Ratcliff says he’s ready to enjoy it.

“The dreams and aspirations that I had coming into the sport were much less than what it actually turned out to be,” Ratcliff says. “So I’m just extremely thankful for so many people giving me opportunities and NASCAR in general. I think everyone in the garage should sit back and reflect on what it means to have an opportunity to go to work every day, doing something you enjoy and get paid for. I know that it’s been a lot of effort over the last 75 years for them to continue this sport and grow in the way that it is and what it’s turned into. So, to be a part of that, it’s been just awesome. It’s been a great career for me.”