Anthony "Rumble" Johnson, a legendary MMA fighter who battled an unspecified illness, has passed away at the age of 38.

Bellator MMA, the fighting promotion with which Johnson most recently competed, confirmed his death on Sunday.

"The Bellator family is devastated by his untimely passing," the promotion said, "and we send our condolences to his family and friends during this difficult time."

During a 15-year MMA career in which he held a 23-6 record, Johnson fought for the UFC title twice, both times losing to Daniel Cormier.

Those matches moved down to light heavyweight in 2015 and 2017, where Johnson eventually settled after debuting in the welterweight division.

He last scored a knockout victory over Jose Augusto Azevedo at Bellator 258 in May 2021, that earned him a light heavyweight title shot against Vadim Nemkov

Late last month, Johnson's manager, Ali Abdelaziz, said the fighter was "going through some health problems right now."

"RIP Anthony 'Rumble' Johnson," UFC fighter Michael Chiesa wrote on Twitter on Sunday. “One of the most prolific KO artists we have ever seen in our game.

MMA fighter Anthony ‘Rumble’ Johnson dies at 38