Tommy Morrison, who became the heavyweight champion with a win over George Foreman in 1993, died at the age of 44 on Sunday in a Nebraska hospital.
Morrison tested positive for the HIV virus in 1996.
The last 20 years of the brash boxer's life would be defined by extensive legal troubles, erratic behavior and mounting health problems. Morrison would later claim that he never tested positive for the virus that causes AIDs, even as he was hospitalized during the last days of his life.
His longtime promoter, Tony Holden, confirmed that "the Duke" had died.
"Tommy's a very stubborn person and he views things the way he wants to view things. That's his right and privilege," Holden said. "All through his career, him and I would come not to physical blows but disagreements on certain things. We always ended up friends. That was Tommy.
"That's the way Tommy took off after he was told he was HIV-positive," Holden added. "When he first was told, I was taking him to seek treatment and to different doctors around the country. And then he started research on the Internet and started saying it was a conspiracy. He went in that direction and never looked back."