Angelo Dundee, who for two decades was Muhammad Ali's trainer, has died aged 90.
Dundee worked with 15 world champions, including Sugar Ray Leonard and George Foreman but it is his work with Ali that stands out the most.
He worked with him in his most famous fights, including 'The Rumble in the Jungle' against Foreman in 1974.
Together they crafted the "rope-a-dope" technique which helped Ali dethrone Foreman in the famous fight in Zaire.
The Miami Herald reported that Dundee died of a heart attack in a rehabilitation centre after initially being admitted to the hospital with a blood clot.
Dundee was considered a quick thinker and the best fight strategist in the sport.
He began working with Leonard in 1976 before helping Foreman win the heavyweight title in 1994 at the age of 45.
Dundee's death comes as questions surround the health of Ali.
In November, the heavyweight great was briefly hospitalised in Phoenix, where doctors treated him for dehydration.