Former world heavyweight champion Muhammad Ali, whose record-setting boxing career, unprecedented flair for showmanship and controversial stands, has died aged 74.

One of the best-known figures of the 20th century, Ali’s death was confirmed in a statement issued by his family on Friday evening, a day after he was admitted to a Phoenix-area hospital with a respiratory ailment.

The cause of death or the name of the hospital where he died were not immediately disclosed.

Ali had long suffered from Parkinson’s disease, which impaired his speech and made the once-graceful athlete almost a prisoner in his own body.

Even so, Ali’s youthful proclamation of himself as “the Greatest” rang true until the end for the millions of people worldwide who admired him for his courage, both inside and outside the ring.

“A part of me slipped away, the greatest piece,” George Foreman, a former heavyweight boxer and one of Ali’s most formidable opponents in the ring, said on Twitter.

Roy Jones Jr, a former champion boxer who grew up during Ali’s prime, said: “My heart is deeply saddened yet both appreciative and relieved that the greatest is now resting in the greatest place.”