"The Greatest of All Time," Muhammad Ali transcended sports and became a once-in-a-lifetime personality.

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Muhammad Ali and his compatriot and titleholder George Foreman in Kinshasa on Sept. 30, 1974.

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American heavyweight boxing champion Joe Frazier kept his title at the end of the fight called the "match of the century" against his compatriot Muhammad Ali at the Madison Square Garden, in New York, March 8 1971.

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Perspiration flies from the head of George Foreman as he takes a right from challenger Muhammad Ali in the seventh round in the match dubbed Rumble in the Jungle in Kinshasa, Zaire, on Oct. 30, 1974.

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World heavyweight champion Larry Holmes, left, pounds challenger Muhammad Ali in the corner during championship fight in Las Vegas, Nev., Thursday night, Oct. 2, 1980.

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Challenger Muhammad Ali, right, gives WBC heavyweight champion Larry Holmes a wide-eyed look during their WBC championship title fight, October 2, 1980, in Las Vegas, Nevada.

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Muhammad Ali, left, is shown being pummeled against the ropes by WBC heavyweight champion Larry Holmes during their Las Vegas, Nevada fight of October 2, 1980. Holmes scored an 11th round TKO to retain his WBC heavyweight title.

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Heavyweight Champion Muhammad Ali falls against the ropes as Jimmy Young moves in during championship bout at Landover, Md., on Friday, April 30, 1976.

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Boxer Joe Frazier is being directed to the ropes by referee Arthur Marcante after knocking down Muhammad Ali during the 15th round of the title bout in Madison Square Garden in New York City on March 8, 1971. Frazier won the bout over Ali by decision.

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In this March 8, 1971 photo, boxer Joe Frazier lands a left to the jaw of Muhammad Ali during their title bout at New York's Madison Square Garden. Frazier won on a unanimous decision and retained his heavyweight title.

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Joe Frazier hits Muhammad Ali with a left during the 15th round of their heavyweight title fight at New York's Madison Square garden in this March 8, 1971 photo.

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Joe Frazier stands over Muhammad Ali in the 15th round of their heavyweight title fight at New York's Madison Square garden in this March 8, 1971 photo.

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Defeated Canadian George Chuvalo clasps Muhammad Ali's arm in the ring at Toronto's Maple Leaf Gardens after the heavyweight champion scored a unanimous decision in their 15-round bout on March 29, 1966 in Toronto.

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Muhammad Ali lands a right from long range against George Chuvalo in the third round of their Toronto bout on March 29, 1966.

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This is a Oct. 30, 1974 file photo of Muhammad Ali winces as he takes a George Foreman left to the jaw in fifth round of their heavyweight championship bout in Kinshasa, Zaire. Ali knocked out Foreman in the eighth round to regain the title.

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This is a Wednesday , Sept. 11, 1974 file photo of Muhammad Ali, right, as he boxes with sparring partner Larry Holmes during his first workout at the N'Sele, Zaire training camp in preparation for his title bout with heavyweight champion George Foreman

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On Oct. 30, 1974, Muhammad Ali watches as defending world champion George Foreman goes down to the canvas in the eighth round of their WBA/WBC championship match in Kinshasa, Zaire, on Oct. 30, 1974. Foreman was counted out by the referee and Ali regained the world heavyweight crown by knockout in the bout dubbed "Rumble in the Jungle."

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This was the scene in the ring at Caesars Palace prior to the start of the Larry Holmes-Muhammad Ali heavyweight title bout in Las Vegas, Oct. 3, 1980. Ali keeps up a constant bid to upset Holmes, the champion on the left, as referee Richard Green attempted to give the fighters their instructions. Ali lost to Holmes in his bid to win the heavyweight title a fourth time.

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Heavyweight champion Larry Holmes, seemed to pepper Muhammad Ali at will in battle at Caesars' Palace in Las Vegas Thursday, Oct. 3, 1980. Holmes successfully defended his crown when Ali failed to answer the bell at the start of the 11th round.

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Canadian champion George Chuvalo sports a wide, long cut on his forehead, as he and Muhammad Ali talk to newsmen after their heavyweight battle in Vancouver, British Columbia, Canada on Monday, May 2, 1972. Ali won a unanimous decision over Chuvalo in 12 rounds.

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Muhammad Ali after fight with George Chuvalo in Vancouver, British Columbia, Canada on May 1, 1972.

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Former world heavyweight champion Muhammad Ali lands a hard right to the head of George Chuvalo in the 11th round of their fight on May 1, 1972 in Vancouver, British Columbia, Canada. Ali won a unanimous decision.

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George Chuvalo, Canadian heavyweight champion, connects with a left to the head of Muhammad Ali, former heavyweight champion in action in the first round of their scheduled 12-round fight on Monday, May 1, 1972 at Vancouver's Pacific Coliseum in Vancouver, British Columbia, Canada.

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A serious Muhammad Ali has his hands raised in victory after winning a unanimous decision over Canadian heavyweight champion George Chuvalo in 12 rounds at Vancouver, B.C., Canada on May 1, 1972.

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Muhammad Ali appears to be sizing up George Chuvalo's head as a target early in their Toronto fight on Tuesday, March 30, 1966 in Toronto. The heavyweight champion, who won a unanimous decision, told newsmen afterwards that Chuvalo's head was harder than anything he hit in training and held up his bruised right hand.

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Champion Muhammad Ali throws a right to George Chuvalo's head and cocks his right during a mid-ring exchange midway in their Toronto match on March 29, 1966 in Toronto. Ali won a unanimous decision.

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Heavyweight boxing champion Muhammad Ali holds a tennis racket over tennis player Bjorn Borg in July of 1979.

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Muhammad Ali holds the torch before lighting the Olympic Flame during the Opening Ceremony of the 1996 Centennial Olympic Games in Atlanta, Georgia, on July 19, 1996.

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Muhammad Ali at home in September of 1980.

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Muhammad Ali delivers a press conference on Nov. 19, 1974 in Paris.

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Muhammad Ali, left, and Joe Frazier, center, shown in action at Madison Square Garden, New York on March 8, 1971.

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Muhammad Ali during a press conference on March 4, 1976, in Paris about his book, "The Greatest."

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Muhammad Ali signs the french translation of his book, "The Greatest," in Paris on March 4, 1976.

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Muhammad Ali in Kinshasa, Zaire, on Sept. 20, 1974.

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Muhammad Ali stands with his mother Odessa Grady Clay during a training session on Oct. 27, 1974, three days before the heavyweight world championship in Kinshasa. On Oct. 30, 1974. Ali knocked out George Foreman in a clash of titans known as the "Rumble in the Jungle."

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Muhammad Ali is escorted at his training center 11 days before the heavyweight world championship in Kinshasa, Zaire on Oct. 19, 1974.

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Muhammad Ali during a press conference after the heavyweight world championship in Kinshasa on Oct. 30, 1974. Ali knocked out George Foreman in a clash of titans known as the "Rumble in the Jungle."

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Muhammad Ali gestures during a press conference three days before the heavyweight world championship in Kinshasa on Oct. 27, 1974.

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Muhammad Ali gestures during a press conference three days before the heavyweight world championship in Kinshasa on Oct. 27, 1974.

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Former heavyweight world boxing champion Muhammad Ali prays on Oct. 5, 1986 at the Mosque of Muhammad Ali Pasha or Alabaster Mosque in Cairo, Egypt.

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Former heavyweight world boxing champion Muhammad Ali speaks on Oct. 5, 1986 during a press conference at the Marriott hotel in Cairo, Egypt, to promote a new luxury sports car called the "Ali".

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Muhammad Ali against Al "Blue" Lewis in Dublin, Ireland.

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Jack Nicklaus meets Muhammad Ali during the US PGA Championship at Valhalla Golf Club in Lexington, Kentucky, on Aug. 8, 1996.

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Floyd Patterson rubs Muhammad Ali's shoulder as he says hello on April 1, 1993 at a gathering of boxers for the World Boxing Council awards ceremony.

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World heavyweight boxing champion, Cassius Clay, signs autographs outside the Trans-Lux Theater on Broadway at 49th Street, New York City, March 1, 1964, after he had watched a screening of the films showing his title victory over Sonny Liston in Miami Beach, February 25.

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Challenger Cassius Clay is shown in rare form as he signed to meet heavyweight boxing champion Sonny Liston. The signing took place at the Denver Hilton Hotel, November 6, 1963.

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Muhammad Ali (Cassius Clay), the "Louisville lip," holds up eight fingers in London June 19, 1963 as he predicts the number of rounds it will take him to knock out Sonny Liston if he should get a chance at the world heavyweight championship.

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Muhammad Ali (Cassius Clay), right, Louisvilles blabbermouth boxer, and British heavyweight champion Henry Cooper seem to be trying to out shout each other at weigh-in June 18, 1963 in London for their heavyweight fight the same evening.

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Young heavyweight boxer Cassius Clay plants a kiss on his mother's cheek, April 4, 1963, at their home just east of Louisville, Ky.

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Heavyweight Muhammad Ali (Cassius Clay) uses fingers instead of rhyme March 6, 1963 to show his intention of Downing Doug Jones in sixth round of their scheduled 10 round match March 13 at New York's Madison Square Garden.

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Heavyweight boxer Cassius Clay predicts the round his bout with Charley Powell will end, while relaxing in his hotel room in Pittsburgh, Jan. 17, 1963.

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Young heavyweight boxer Cassius Clay points to a sign he wrote on a chalk board in his dressing room before his fight against Archie Moore in Los Angeles, Nov. 15, 1962, predicting he'd knock Moore out in the fourth round, which he went on to do. The sign also predicts Clay will be the next champ via a knockout over Sonny Liston in eight rounds.

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Young heavyweight fighter Cassius Clay is seen with his trainer Angelo Dundee at City Parks Gym in New York, Feb. 8, 1962.

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Young heavyweight fighter Cassius Clay is seen at City Parks Gym in New York, Feb. 8, 1962.

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Cassius Clay, 19, last year's Olympic gold medalist who recently turned professional, connects with a straight right to the jaw of Kolo (Duke) Sabedong during a 10-round heavyweight bout in Las Vegas, Nevada June 26, 1961. Clay, who maintains he will be world champion before he turns 21, scored a unanimous decision, to run his professional winning streak to seven straight.

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Cassius Clay, in white trunks, is shown in his professional boxing debut, October 29, 1960, in Louisville's Freedom Hall, against Tunney Hunsaker - a part-time fighter and the full-time police chief of Fayetteville, West Virginia.

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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.

Credit: AP

Cassius Clay, 18, from Louisville, Ky., throws a right at Tony Madigan of Australia, left, during the light heavyweight boxing semifinals at the Summer Olympic Games in Rome, Italy, Sept. 3, 1960. Clay won the bout with all five votes of the judges.

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Cassius Clay is new Boxing World Champion. AP Photo shows him during a training with Johnny Hampton in 1959.

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Boxer Cassius Clay is pictured at the Induction Center in Houston Texas on April 28, 1967.

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Johnny Carson, star of NBC-TV's "Tonight" show, watches world heavyweight boxing champ Muhammad Ali hamming it up for a photographer in New York, Feb. 10, 1967.

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Heavyweight champion Cassius Clay feigns being knocked down by his brother Rudy at the end of an exhibition bout they put on for the patients at Hines Veterans Hospital in Chicago, Illinois, Feb. 24, 1965.

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Heavyweight champion Cassius Clay admires the fist of boxing great Jack Dempsey as they gag it up for the camera at the Boxing Writers' Association's annual dinner in New York, Jan. 17, 1965.

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Cassius Clay, clutching a rope, heads toward a car while one of his handlers pours honey on the ground, Nov. 9, 1964. They were waiting for the arrival of Sonny Liston for a physical examination in Boston.

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Heavyweight champion Muhammad Ali, right, shakes hands with challenger Sonny Liston after their formal signing for their title rematch to take place Nov. 16 at the Boston Garden, Boston, Ma., Sept. 14, 1964. The signing is witnessed by Herman Greenberg, center, chairman of the Massachusetts Boxing Commission, at a Boston motel.

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Cassius Clay is new Boxing World Champion. The photo shows him welcomed by young fans when returning from Great Britain on March 16, 1964.

Credit: ASSOCIATED PRESS/ JACK KANTHAL

World heavyweight boxing champion Cassius Clay signs autographs outside the Trans-Lux Theater on Broadway at 49th Street in New York, March 1, 1964 after he had watched a screening of the films showing his title victory over Sonny Liston in Miami Beach on Feb. 25.

Credit: AP

Sugar Ray Robinson, left, and Cassius Clay, right, gesture like champs on the way to the dressing room after Clay's technical knockout victory in the seventh round over heavyweight champion Sonny Liston in Miami Beach, Florida, February 25, 1964. In the center, an emotional Clay handler, Drew "Bundini" Brown, escorts the new champ.

Credit: AP / Harry Harris

Cassius Clay, young heavyweight fighter, thrusts his fist out on Feb. 19, 1964, as he tells a crowd at Surfside, Fla., how he'll hit champion Sonny Liston in their upcoming bout at Miami Beach. Clay and his followers paid an unexpected visit to Liston's Surfside camp.

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Boxer Cassius Clay lifts Ringo Starr, one of the Beatles into the air while the singers visited Clay's camp in Miami Beach, Fla. , February 18, 1964. Others are, from left: Paul McCartney, George Harrison, and John Lennon.

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The Beatles, from left, Paul McCartney, John Lennon, Ringo Starr, and George Harrison, take a fake blow from Cassius Clay while visiting the heavyweight contender at his training camp in Miami Beach, Fla. on February 18, 1964.

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Muhammad Ali (Cassius Clay), age 22, celebrates with a cake decorated with a boxing ring and two fighters in Miami Beach, Fla., January 17, 1964. Sonny Liston in a horizontal position and Ali as the winner. A group of friends gathered to help him celebrate including his father and mother.

Credit: AP/ John Rooney

Muhammad Ali (Cassius Clay) at The Bitter End, a Greenwich Village spot in New York's Bohemian Quarter on March 7, 1963. The reason the man who calls himself the "greatest" as a fighter, was chosen as the winner during a verse reading session with the village's "inner circle of poets" competing.

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Victorious Muhammad Ali (Cassius Clay) holds up three fingers and a fist in his dressing room in Pittsburgh, on Jan. 25, 1963, following his three-round knockout of Charley Powell.

Credit: ASSOCIATED PRESS/ Ed Kolenovsky

Former heavyweight champion Muhammad Ali (Cassius Clay), right, with his attorney, Charles Morgan Jr. of Atlanta, as they leave the Federal Court Building on June 2, 1969 in Houston. They got a two-day delay on a motion to postpone the hearing on a Government wiretap involving Clay.

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Boxer Cassius Clay is pictured at the Induction Center in Houston Texas on April 28, 1967. (

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Heavyweight boxing champion Muhammad Ali (Cassius Clay) during a poolside press conference at his quarter on May 24, 1965 in Lewiston nearby Auburn, Maine.

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Heavyweight Champion Muhammad Ali displays pictures of Elijah Mohammad, right and Elijah's messenger William Far, left during an interview at Lewiston nearby Auburn on May 23, 1965. Ali discussing rumors of a possible attempt on his life, said he is only afraid of two men, those whose pictures he shows. He meets Sonny Liston for the bout in Lewiston, Maine, on Tuesday.

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Heavyweight boxing champion Muhammad Ali as he left Boston City Hospital for a press conference on Nov. 27, 1964 in Boston. Clay has been recuperating from a hernia operation performed on November 13.

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Heavyweight boxer Cassius Clay is seen in 1964 with his wife Sonji Clay.

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Muhammad Ali holds what he thinks is a resemblance to champion Sonny Liston at a party at the Las Vegas Press Club on July 19, 1963.

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Muhammad Ali at the wheel of a car on April 2, 1963.

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Jackie Robinson, former Brooklyn Dodgers baseball player, hits a punching bag held by heavyweight boxing champion Cassius Clay in a New York gym during his visit on March 13, 1963.

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Heavyweight Muhammad Ali (Cassius Clay) poses on March 6, 1963 at New York's Pennsylvania Station after arrival from Florida. Ali is scheduled to meet Doug Jones at New York's Madison Square Garden on March 13.

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Cassius Clay, seen Feb. 28, 1963 in Miami

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Muhammad Ali (Cassius Clay) grins happily and clasps his hands in the victory salute in his dressing room on Jan. 24, 1963 in Pittsburgh after fulfilling his prediction of scoring a third-round knockout in 10-round heavyweight fight with Charley Powell.

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Muhammad Ali (Cassius Clay) the fast talking heavyweight who predicts what round he will knock out his opponent and then does it, blows out the candles on his birthday cake on Jan. 17, 1963 in Pittsburgh.

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Muhammad Ali (Cassius Clay) the young heavyweight from Louisville, Ky., shadow boxes on Nov. 13, 1962 in the final stages of his preparations to fight Archie Moore in the Los Angeles Sports Arena November 15.

Credit: AP

Eighty-five pound Cassius Marcellus Clay, Jr., is shown posing at age 12, prior to his amateur ring debut in 1954, a three-minute, three-round split decision over another novice named Ronnie O'Keefe, in Louisville, Kentucky.

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Muhammad Ali in March 1964.

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Never for a loss of words, Muhammad Ali (Cassius Clay) answers questions during a news conference after his technical knockout win over world heavyweight champ Sonny Liston in Miami Beach, Florida on Feb. 25, 1964.

Credit: AP

Muhammad Ali, or Cassius Clay at the time, strikes a familiar pose as he shouts "I am the greatest," as he leaves the ring, arms raised, following his defeat of former heavyweight boxing champion Sonny Liston in Miami Beach, Fla., February 25, 1964.

Credit: AP

Cassius Clay's handlers hold him back as he reacts after he is announced the new heavyweight champion of the world on a seventh round technical knockout against Sonny Liston at Convention Hall in Miami Beach, Fla., on Feb. 25, 1964.

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Heavyweight challenger Muhammad Ali (Cassius Clay) lets out a howl as he steps to the box office Feb. 22, 1964 in Miami Beach, Florida, three days prior to fighting Sonny Liston.

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Muhammad Ali on Feb. 1, 1964 in Miami Beach, Florida.

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Muhammad Ali (Cassius Clay) catches a medicine ball in the midsection as he trains for his Feb. 25 heavyweight championship bout with champion Sonny Liston.

Credit: ASSOCIATED PRESS/ John Lindsay

Boxer Cassius Clay draws a mixed audience reaction at a rally in upper Manhattan, New York, Aug. 10, 1963, as he gives black Muslim leader Malcolm X a little verbal competition.

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Muhammad Ali (Cassius Clay) faces newsmen in the dressing room at Madison Square Garden in New York on March 13, 1963, after winning a unanimous decision over Doug Jones in a 10-round bout.

Credit: ASSOCIATED PRESS/ Don Brinn

Muhammad Ali (Cassius Clay) the young heavyweight from Louisville, Ky., shadow boxes on Nov. 13, 1962 in the final stages of his preparations to fight Archie Moore in the Los Angeles Sports Arena Nov. 15.

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Former heavyweight champion Muhammad Ali sticks out his right glove as he takes a breather during workouts at his training camp in Miami Beach, Fla., on Oct. 6, 1970 preparing for his non-title fight with Jerry Quarry in Atlanta, Ga., on October 26.

Credit: ASSOCIATED PRESS/ Ed Kolenovsky

Muhammad Ali (Cassius Clay), left, laughs along with his attorney Hayden Covington after a small joke Clay pulled on May 8, 1967. Ali hid in a door way and some of his followers told Covington that he had been picked up by U.S. Marshalls. The joke brought on the big laugh. Ali was indicted by a Federal Grand Jury on a charge of refusing to be drafted into the armed services.

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Heavyweight champion Muhammad Ali raises his hand in a blessing gesture as he walks down the corridor at the Armed Forces Examining and Entrance Station in Houston, April 28, 1967.

Credit: AP/ John Rooney

Heavyweight champion Muhammad Ali (Cassius Clay), left, and his group walk through snow as they cross New York's Eighth Avenue on March 22, 1967 on their way to Madison Square Garden and weigh-in for his title fight with Zora Folley.

Credit: ASSOCIATED PRESS/ Ed Kolenovsky

World heavyweight champion Cassius Clay, (Muhammad Ali) as he does sit ups as he started his first work out on Tuesday, Feb. 22, 1967. Ali started his training after a two-week rest from his heavyweight fight with Ernie Terrell. He is training now for his title fight with Zora Folley in New York on March 22.

Credit: ASSOCIATED PRESS/ Ed Kolenovsky

Songstress Eartha Kitt stops by Muhammad Ali's training camp in Houston, Texas on Feb. 2, 1967 to wish him success on next Monday night when he battles Ernie Terrell for the world's heavyweight boxing championship in the Astrodome.

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Muhammad Ali gets his gloves laced outside a boxing ring in Houston, Texas in February 1967. Ali is training for a Feb. 6 championship title fight with Ernie Terrell.

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Muhammad Ali is shown training in the ring in Houston, Texas in February 1967. Ali is training for the Feb. 6 championship title fight with Ernie Terrell.

Credit: AP/ Peter Kemp

World Heavyweight Champion Cassius Clay, who wishes to be known as Muhammad Ali, stretches out on two chairs in his London Hotel, on May 20, 1966, after completing his serious training for the following night's bout against British Heavyweight Champion Henry Cooper at Highbury Stadium in London.

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Cassius Clay is a happy young man in his dressing room after knocking out Archie Moore in the exact round he predicted he would, the fourth, at Los Angeles, Nov. 17, 1962.

Credit: ASSOCIATED PRESS/ Anonymous

Champion Muhammad Ali (Cassius Clay), doesn't wait for Dr. Donald J. Romeo's verdict to pass the word he's in shape to defend his heavyweight title against Floyd Patterson on Nov. 21, 1965 in Las Vegas, Nev. Ali underwent a final physical examination today at the hands of Dr. Romeo, chief medical examiner of the Nevada Athletic Commission.

Credit: AP/ Larry Stoddard

Pointing a finger as he signs autographs at Black Muslim convention on Feb. 27, 1965 in Chicago, Muhammad Ali makes like his other self, Cassius Clay, with a short speech. He had just boxed an exhibition bout with his brother, Rudy.

Credit: ASSOCIATED PRESS/ Anonymous

Banner headlines proclaiming his feat occupied the attention of heavyweight champion Cassius Clay at his motel at nearby Auburn. Clay successfully retained crown via a one-round KO over Sonny Liston in Lewiston, Me., on May 26, 1965.

Credit: AP/ Anonymous

Heavyweight Champion Muhammad Ali (Cassius Clay) takes time out from training at Chicopee, Mass. on May 13, 1965 for his title bout with Sonny Liston to sit on rocks in brook and enjoy a bowl of fruit. Ali found the spot while out doing his road work. The title fight is scheduled for May 25 at Lewiston, Maine.

Credit: ASSOCIATED PRESS/ Frank Curtin

World Heavyweight Champion Muhammad Ali (Cassius Clay) gestures during a press conference at his training camp in Chicopee, Mass. on May 4, 1965. Clay will meet ex-titlist Sonny Liston in a rematch scheduled for May 25 at Boston garden. Clay refused to name the round in which he predicts he will knock out Liston. At left is Stepin Fetchit former stage and screen star.

Credit: AP/ Bill Chaplis

World heavyweight champion Muhammad Ali (Cassius Clay) drinks coffee while reading newspaper at Schine Inn in Chicopee, Mass., on May 3, 1965, where he will train for rematch with ex-titlist Sonny Liston. The match is scheduled for May 25 at Boston Garden.

Credit: AP

Muhammad Ali (Cassius Clay) at the start of the trek to Boston of the entourage in Miami , Florida on April 30, 1965.

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Muhammad Ali (Cassius Clay) at the start of the trek to Boston of the entourage in Miami , Florida on April 30, 1965. Ali said he just drives from big town to big town, never mind the map.

Credit: AP/ Les Stoddard

Muhammad Ali, world heavyweight champion, claps after leader Elijah Muhammad speaks at Black Muslim convention on Feb. 26, 1965 in Boston. Clay took Muhammad Ali as name when he joined Muslims.

Credit: ASSOCIATED PRESS/ Stan Grain

Eager to shake his hand, Nigerians swarm round world heavyweight boxing champion Muhammad Ali as he sits atop his car during the drive to his hotel after arriving at the airport in Lagos, Nigeria on June 1, 1964. Ali, who is on a tour of West Africa, led the crowd in cheering himself as "King of the World."

Credit: ASSOCIATED PRESS/ MI

Former world boxing champ, Muhammad Ali came across with some characteristic expressions during a news conference on Monday, April 10, 1972 in New York after signing for a May 1 fight with George Chuvalo, right, of Vancouver. The pair will face each other at the pacific coliseum in a non-title 12-round-bout in Vancouver, B.C. Canada.

Credit: AP/ Charles Kolenovsky

Credit: ASSOCIATED PRESS/ Ed Kolenovsky

Muhammad Ali (Cassius Clay) with his chief attorney Hayden Covington, right, on June 19, 1967 in Houston, Tex., as they wait for the elevator to take them up to the Federal Court and Clay's trial. Clay goes to trial on a federal indictment which charges him with refusing to be inducted into the armed services.

Credit: ASSOCIATED PRESS/ Charles Harrity

Muhammad Ali (Cassius Clay), former world heavyweight boxing champion, leans into a battery of microphones waiting for a reply at an anti-war rally on May 10, 1967 at the University of Chicago in Chicago.

Credit: ASSOCIATED PRESS/ Ed Kolenovsky

A uniformed member of the armed forces explains proceedings to Heavyweight Champion Muhammad Ali (Cassius Clay) at the induction center in Houston on April 28, 1967. Clay arrived at the center along with other inductees and went immediately into a room where the examinations are conducted.

Credit: ASSOCIATED PRESS

World Heavyweight Boxing Champion Muhammad Ali (Cassius Clay) in 1966.

Credit: AP/ NAP

Boxer Cassius Clay (Muhammad Ali) beats his chest in triumph after toppling Britain's Beatles at his training camp in Beach, Fla., Feb. 18, 1964. The Beatles, left to right: Paul McCartney; John Lennon; George Harrison and Ringo Starr, were on Holiday in the resort after their American tour. Clay will meet heavyweight champion Sonny Liston in Miami Beach on Feb. 25.

Credit: AP

In this Feb. 6, 1967, file photo, World Heavyweight Champion Cassius Clay, left, and Ernie Terrell stand face to face during a weigh-in for the title fight tonight in Houston, Texas.

Credit: AP

Never at a loss for words, Cassius Clay holds forth at ringside in Las Vegas, Nev., July 22, 1963, shortly before the start of the heavyweight title fight between Sonny Liston and Floyd Patterson. Clay hopes to be matched against the winner.

Credit: AP/ STR

A 1965 image of Boxer Muhammad Ali in the USA, with his first wife Sonji Roi.

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