Muhammad Ali was the subject of countless photographs during an amazing boxing career which saw him transcend the world of sport.
But few photographers ever got as close to "The Greatest" as the renowned Sonia Katchian.
Here, BBC Sport presents just a few of the photos in which she captures the essence of Ali both in the gym and away from the ring.
Katchian's work is featured in a new exhibition at Proud Central, 5 Buckingham Street, London, WC2N 6BP, from 14 March to 11 May.
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