1972: Muhammad Ali during training for his fight with Al 'Blue' Lewis held in Dublin, Republic of Ireland in 1972. (Photo by Getty Images)
Ali's Girls
19th December 1978: Heavyweight boxer Muhammad Ali with his daughters Laila (9 months) and Hanna (2 years 5 months) at Grosvenor House. (Photo by Frank Tewkesbury/Evening Standard/Getty Images)
Cassius Clay vs Sonny Liston
25 MAY 1965: Cassius Clay defeats Sonny Liston with a 1st round knockout.(Credit: Allsport Hulton/Archive)
1996 Olympics
19 Jul 1996: Muhammad Ali holds the torch before lighting the Olympic Flame during the Opening Ceremony of the 1996 Centennial Olympic Games in Atlanta, Georgia. (Credit: Michael Cooper)
1964: Cassius Clay vs Sonny Liston
FEBRUARY 25, 1964: Cassius Clay (now Muhammad Ali) in action against Sonny Liston during their heavyweight title fight at Miami Beach, Florida. Clay won the contest, becoming world champion, when Liston failed to come out at the start of the seventh round. ( Central Press/Getty Images)
Give Me Five
27th May 1963: American Heavyweight boxer Cassius Clay (later Muhammad Ali) lying on his hotel bed in London. He holds up five fingers in a prediction of how many rounds it will take him to knock out British boxer Henry Cooper. ( Len Trievnor/Express/Getty Images)
Ali In Training
American heavyweight boxer Muhammad Ali throws bare-handed punches in the ring while in training for his fight against Brian London, London, England, August 1966. (McPhedran/Hulton Archive/Getty Images)
Clay And The Beatles
February 1964: American heavyweight boxer Cassius Clay poses in the ring in mock victory over British pop group The Beatles, meeting the press in New York during an American tour. (Keystone/Getty Images)
Ali Address
2nd December 1974: World Heavyweight Champion boxer Muhammad Ali addressing a Nation of Islam meeting at the New Victoria Theatre in London. (Tim Graham/Evening Standard/Getty Images)
HBO Films And The Muhammad Ali Center Co-Host The U.S. Premiere Of "Muhammad Ali's Greatest Fight"
LOUISVILLE, KY - OCTOBER 02: Len Amato, Laila Ali, Muhammad Ali and Donald Lassere appear as HBO Films and the Muhammad Ali Center co-host the U.S. Premiere of "Muhammad Ali's Greatest Fight" at Muhammad Ali Center on October 2, 2013 in Louisville, Kentucky. ( Michael Hickey/Getty Images for HBO)
Muhammad Ali
American boxer Cassius Clay (Muhammad Ali) in the ring after defeating Sonny Liston in their world heavyweight title fight at Miami Beach, Florida, 25th February 1964. (Express/Hulton Archive/Getty Images)
Cooper And Clay
British Heavyweight champion Henry Cooper (1934 - 2011, left) with American boxer Cassius Clay (later Muhammad Ali) after their non-title fight at Wembley Stadium, London, 18th June 1963. Clay won the match by a technical knockout after Cooper sustained a cut under his left eye. (Central Press/Hulton Archive/Getty Images)
The Grand Gala Hilton VIP Reception Held At The Muhammad Ali Center
LOUISVILLE, KY - MAY 05: Former Boxer Muhammad Ali poses as he attends the Grand Gala Hilton VIP reception held at the Muhammad Ali Center on May 5, 2006 in Louisville, Kentucky. (Paul Hawthorne/Getty Images)
Boxing Beatles
22nd February 1964: British pop group The Beatles, from left to right; Ringo Starr, John Lennon (1940 - 1980), George Harrison (1943 - 2001) and Paul McCartney; in the ring with champion American boxer Cassius Clay, whilst in Miami. (Photo by Keystone/Getty Images)
MUHAMMAD ALI
UNDATED: JOE FRAZIER, GEORGE FOREMAN AND MUHAMMAD ALI. Mandatory Credit: Gray Mortimore/ALLSPORT
Ali In London
American boxer Muhammad Ali looks out over London from the top of the Post Office Tower, 25th July 1966. Ali is in Britain to defend his World Heavyweight title against Brian London. (Keystone/Hulton Archive/Getty Images)
Ali and Nicklaus
Muhammed Ali meets Jack Nicklaus. (Getty Images_
Cassius Clay and Child
4th June 1963: American heavyweight boxer Cassius Clay in a one round non-title fight with 6 year old Patrick Power. Young Patrick is taking boxing lessons in order to combat bullies at home. (Keystone/Getty Images)
Training Ali
1965: Muhammad Ali (Cassius Clay) on the punch ball at his training camp in preparation for a defence of his Heavyweight crown. Mandatory Credit: Allsport Hulton/Archive
Laila Ali With Father Muhammad Ali
Boxer Laila Ali poses with her father, former heavyweight champion Muhammad Ali, after she defeated Suzy Taylor in two rounds at the Aladdin Casino in Las Vegas, Nevada, August 17, 2002 (Scott Halleran/Getty Images)