MMA Star Anthony 'Rumble' Johnson Dead After Complications from Cancer and Rare Autoimmune Disease

Josh Hedges/Zuffa LLC/getty

MMA star Anthony "Rumble" Johnson has died. He was 38.

Bellator MMA, the last promotion Johnson fought in, announced the news of his death in a social media statement on Sunday.

"It is with great sadness we acknowledge the passing of Anthony 'Rumble' Johnson," the statement read. "The BELLATOR family is devastated by his untimely passing and we send our condolences to his family and friends during this difficult time."

Johnson died due to a result of organ failure caused by complications from non-Hodgkin's lymphoma and hemophagocytic lymphohistiocytosis, a rare autoimmune disorder, according to Yahoo Sports.

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In September 2021, only months after his last match in May of that year, Johnson posted a message on Instagram letting fans know he had an undisclosed illness.

"Really wish I could go into detail about how ill I truly am," Johnson wrote. "Just know I need as many prayers as I can get and I'll see you in 2022 God willing. Never been this afraid of anything in my life but I've remained strong with the support of friends and family."

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While Johnson would go on to note in May 2022 that there were "big improvements" in his health, he later informed fans through a June Instagram post that he had lost weight as a result of his illness.

His manager, Ali Abdelaziz, provided an update to ESPN in October, informing fans that Johnson was not doing well as he asked for prayers for the beloved MMA star.

"He's very strong, spiritually, but pray for him," Abdelaziz told the outlet.

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In his final fight, Johnson defeated Jose Augusto by knockout to end his career with 23 wins and 6 loses.

Before joining Ballator MMA in 2021, Johnson had a 10-year run in the UFC from 2007 to 2017, and competed in two title matches for the UFC light heavyweight title against Daniel Cormier.

Cormier expressed his grief for the late MMA star in a Twitter post on Sunday. "For a guy who struck fear into so many peoples heart Anthony Johnson was a caring person. From random text to check ins during loss. What a person he was, Rumble will be missed," he wrote. "Sometimes life doesn't seem fair. Horrible news."

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UFC president Dana White also remembered Johnson after his death, calling him "a great kid."

"He was always in fun fights and he had that one-punch KO power that not many people ever had. He was a good human being. I send my condolences to his family," he said, per Yahoo Sports.