Four-time heavyweight world champion Evander Holyfield says he is glad to have known Muhammad Ali and learned much from the late boxer's strength in responding to defeats.
One of the most famous athletes in history, Ali died at the age of 74 on Friday, having been hospitalised with respiratory problems earlier in the week.
Ali was beaten five times during his illustrious career, but avenged losses to Joe Frazier, Ken Norton and Leon Spinks.
Holyfield told MSNBC: "To take it upon yourself and say; 'I'm the greatest', you put yourself in a position as a target for people to take pot shots at you.
"This is what Ali did. It's amazing him becoming three-time heavyweight champion of the world. At that time, people thought, 'who could beat three?'.
"I remember in '84 someone asked me: 'Do you want to break his record?'. And I said 'No'.
"He said 'Why?' and I said 'Because that means that I have to lose, I'm not planning on losing. I'm hoping that I never lose'.
"But I found out you have to be stronger to get up from a loss to go on and that's what Ali proved.
"I'm glad to have known Ali, because when I was a kid at eight years old I was told I could be like Ali."
Lennox Lewis, one of Holyfield's great rivals during his fighting career, echoed the sentiments of the 53-year-old with a Twitter tribute of his own.
He wrote: "A giant among men, Ali displayed a greatness in talent, courage & conviction, that most of us will EVER be able to truly comprehend. #RIPAli"