CONCORD, N.C. (AP) — Kyle Busch, a two-time Cup Series champion who won more races than anyone across NASCAR's three national series, has died. He was 41.

The Busch Family, Richard Childress Racing and NASCAR issued a joint statement Thursday saying Busch died after being hospitalized. No cause of death was given.

Busch's family said earlier Thursday that he was hospitalized with a "severe illness," three days before he was to compete in the Coca-Cola 600 at Charlotte Motor Speedway.

Busch was the younger brother of Kurt Busch, a NASCAR Hall of Famer.

"Our entire NASCAR family is heartbroken by the loss of Kyle Busch," the statement said. "A future Hall of Famer, Kyle was a rare talent, one who comes along once in a generation. He was fierce, he was passionate, he was immensely skilled and he cared deeply about the sport and fans.

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The statement went on to say that "throughout a career that spanned more than two decades, Kyle set records in national series wins, won championships at NASCAR's highest level and fostered the next generation of drivers as an owner in the Truck Series. His sharp wit and competitive spirit sparked a deep emotional connection with race fans of every age, creating the proud and loyal 'Rowdy Nation.'"

The news comes 11 days after Busch radioed into his crew near the end of a Cup Series race at Watkins Glen asking a doctor to give him a "shot" after he finished the race. According to the TV broadcast, Busch had been struggling with a sinus cold that was exacerbated by the intense G-forces and elevation changes at the New York road course.

Busch finished the race in eighth place.

Busch competed at Dover last weekend and won the Trucks Series race for Richard Childress Racing. He finished 17th at the NASCAR All-Star race.

"Absolute shock. Very hard to process," veteran NASCAR driver Brad Keselowski posted on social media.

NASCAR driver and former teammate Denny Hamlin posted on social media: "Absolutely cannot comprehend this news. We just need to think of his family during this time. We love you KB."

A polarizing figure known as "Rowdy" and "Wild Thing" for his post-race fights, regular feuds with other drivers and sometimes outlandish behavior, the multi-talented Busch stormed on the Cup Series scene in 2005 by winning Rookie of the Year.

He went on to win championships in 2015 and 2019 for Joe Gibbs Racing.

From Las Vegas, Busch experienced unrivaled success across NASCAR's three national series winning a combined 234 Cup, O'Reilly Auto Parts and Trucks Series races. He had 63 Cup victories along with 102 O'Reilly Auto Parts wins and 69 Trucks victories — both records.

Kyle Busch was viewed as a racing prodigy.

He was said to be ready to race at NASCAR's top level at 16, but a cigarette settlement banned his debut and he had to wait until he was a 18. At the time Kurt Busch said "if you think I'm good, wait until you see my brother."

Busch was fired early in his career by Hendrick Motorsports to make room on the team for Dale Earnhardt Jr.

He moved on to Joe Gibbs Racing where he experienced the vast majority of career success. But Busch was let go when there was no sponsor after the 2022 season and joined RCR, where had struggled to win races.

His lack of success led to a recent spat with former JGR teammate Denny Hamlin, who appeared to criticize Busch on the Actions Detrimental podcast. Hamlin said, "If you're expecting Kyle Busch to just go back to Victory Lane on a regular basis, you are kidding yourselves."

While Hamlin later said he meant no harm by the comments and was just making an observation, Busch took exception and said he could make Hamlin's life "hell" on the racetrack.

While several laps down at last month's race at Kansas, Busch made good on the threat and raced Hamlin hard instead of allowing the race leader to pass. That decision held up Hamlin during a crucial stage of the race and Tyler Reddick wound up winning the race after Hamlin faded late.

After winning the Trucks race at Dover last week and showing an uptick in speed, Busch seemed to make a veiled jab at Hamlin, saying "I guess I just remembered how to drive."

After earning his win at Dover, Busch was asked how many races he wants to win in his career before he stops racing.

"You take whatever you can get, man," Busch said. "You never know when the last one is going to be, so cherish them all — trust me."

The unexpected death is just the latest tragedy to hit NASCAR. Last December, former driver Greg Biffle, his wife and two children and three others died in a plane crash in Statesville, North Carolina.

Busch is survived by wife Samantha and children Brexton and Lennix.