Muhammad Ali through the years

Policeman and mentor Joe Martin Ali as he admires his golden gloves ring in 1959.

Ali relaxes ringside at the 5th Street Gym in Miami Beach prior to his training workout for his world heavyweight title bout with Joe Frazier in 1971.

Ali takes a drink as he trains at the 5th Street Gym in Miami Beach for his world heavyweight title bout with Joe Frazier in 1971.

Ali gave a victory sign as he posed behind the wheel of his 1963 convertible after winning his driver's license back in 1963.

Ali addresses the media during an interview session at the 5th Street Gym in Miami Beach following his training workout for his world heavyweight title bout with Joe Frazier in 1971.

Ali relaxes at his hotel in Miami Beach while in town training workout for his world heavyweight title bout with Joe Frazier in 1971.

Ali signs autographs in his training room during his training for his bout with Leon Spinks at the Superdome in 1978.

Ali poses in a portrait session before making his singing debut in 1960 at the Louisville fairgrounds. Clay sang in the special chorus during his high school days at Central High School.

Ali punches the speed bag at Bruner's Headline Gym as he prepares for his first professional fight in 1960.

entral High students crowd around Ali and his brother Rudy Clay (holding Ali's hand up) after returning home with a gold medal in the 1960 Summer Olympics.

Ali works with a jump rope during a training session in 1971.

Ali embraces ABC sportscaster Howard Cosell in 1975.

Ali embraces his daughter Rasheda Ali after a boxing match in 1981.

Ali signs pictures of himself in his hotel room before a fight against Larry Holmes at Caesars Palace in 1980.

Ali shadow boxes while watching film of his upcoming opponent Larry Holmes in 1980.

Ali (left) interacts with fans prior to his fight against Trevor Berbick in 1981.

Ali talks on a car phone in 1964.

Ali address the media at a local selective service board facility in his hometown of Louisville in 1966.

Ali trains on the fast bag at the 5th Street Gym in Miami Beach during his training for his world heavyweight title bout with Joe Frazier in 1971.

Ali takes his daily three-mile run along a Pennsylvania country road shrouded in early morning fog near his Deer Lake training camp in 1978.

Ali is greeted by then-senator Barack Obama at the Muhammad Ali Center in 2006.

Ali punches the double-end bag at Bruner's Headline Gym as Jimmy Ellis (right) watches in background in 1961.

Ali chats with Joe Frazier in his training room during his training for his bout with Leon Spinks in 1978.

Ali shares a laugh with Joe Frazier in his training room during his training for his bout with Leon Spinks in 1978.

Ali shows off a new pink Cadillac to his mother Odessa Clay in 1960. He bought the automobile for his parents following his first professional fight.

Ali waves to the crowd at a Louisville Cardinals basketball game in 1988.

Ali signs autographs for fans in 1986.

Ali speaks speaks at a rally at the Quinn Chapel AME church in 1967.

Ali appears on NBC's celebrity roast with Dean Martin in 1976.

Ali eats breakfast while watching "Mohammad Messenger of God" in his hotel room before his fight against Larry Holmes in 1980.

Ali prepares for his fight against Trevor Berbick (not pictured) with his brother Rahman Ali in 1981.

Ali (right) fights Trevor Berbick (left) at the Queen Elizabeth Sports Centre. Berwick defeated Ali in ten rounds by unanimous decision and was Ali's last professional fight.

Muhammad Ali stands over fallen challenger Sonny Liston, shouting and gesturing shortly after dropping Liston with a short hard right to the jaw on May 25, 1965.

Ali with his third wife, Veronica Porsche, on their wedding day, Aug. 19, 1977.

Joe Frazier tries to stop the torrent of words coming from Ali during a signing in 1970 before their fight on March 8, 1971.

Ali smashes a right into the jaw of challenger Brian London of Britain, Aug. 6, 1966, in London. Ali knocked out his opponent in the third round.

Two-year-old Shelley Obermuller tugs for the attention of Ali as he signs autographs during a training session in London on May 17, 1966.

A Muhammad Ali training-worn fight robe robe with satin letters on the back spelling out "Muhammad Ali" worn by Ali while training for his third fight with Ken Norton. That fight took place on September 28, 1976 and was the last championship fight ever held at Yankee Stadium.

Ali, holds the "Muhammad Speaks" newspaper with his picture as he and followers of the Muslim sect leave the Las Vegas convention center after weigh-in before his fight against Floyd Patterson on Nov. 22, 1965.

Muhammad Ali during training for his fight with Al 'Blue' Lewis held in Dublin, Republic of Ireland in 1972.

Ali and George Foreman fight in "The Match of the Century" on Oct. 30, 1974 in Kinshasa, Congo.

Shawn Geary held up Hunter Geary, 2, for a kiss from Ali in 2006.

US former world heavyweight boxing champion Muhammad Ali (L) jokes with US actor Will Smith (R) who portrays him in new film "Ali," at the movie's premiere.

A trio of U.S. boxers wear gold medals at the Olympic village in Rome, September 6, 1960. From the left are: Wilbert McClure of Toledo, Ohio, light middleweight; Cassius Clay of Louisville, KY, light heavyweight; and Edward Crook of Fort Campbell, KY, middleweight.

Angelo Dundee with Muhammad Ali, then named Cassius Clay, in Louisville in 1961 after his sixth straight pro win.

Home from the 1960 Olympics, where he was a gold medalist in boxing. Muhammad Ali paid visit to physically challenged children at Kosair Hospital in Louisville, Ky.

Ali, left, smiles at fans while photographer Howard L. Bingham autographs a copy of his book in 1993.

Ali gestures to photographers as he sits at ringside before his daughter Laila's fight in April 1999.

Ali training on Oct. 9, 1974 for his fight in Zaire.

Ali is joined by daughters Jamillah, left, and Rasheda Ali, and his wife Lonnie, right, as they appear before the crowd gathered to celebrate the dedication of the Muhammad Ali Center in 2005.

Ali poses with 1996 Dream Team members from left: Scottie Pippen, Hakeem Olajuwon, Reggie Miller, Shaquille O'Neal, Karl Malone and Gary Payton after receiving the gold medal, which replaces the 1960 gold medal he lost.

Cleveland Williams is spreadeagled on the canvas as referee Harry Kessler sends Ali to a corner during their heavyweight bout at the Astrodome on Nov. 14, 1966.

Andy Warhol, left, is shown photographing Ali, his infant daughter, Hanna, and wife, Veronica on Aug. 18, 1977.

Ali is cheered by Zaire admirers as he drives in downtown Kinshasa for a sightseeing trip in 1974.

Ali crashes a right to the side of Ken Norton's head on Sept. 10, 1973.

Ali jogs along a snow-covered road in Stateline, Nev. on Nov. 21, 1972.

Joe Frazier is directed to the ropes by referee Arthur Marcante after knocking down Ali during the 15th round of the title bout at Madison Square Garden on March 8, 1971. Frazier won the bout by decision.

Muhammad Ali, then known as Cassius Clay, celebrates after winning the heavyweight championship with a knockout of Sonny Liston in the seventh round on Feb. 25, 1964, in Miami Beach, Fla.

Ali throws a punch at Joe Frazier in the 12th round of their fight at Madison Square Garden on Jan. 28, 1974.