Muhammad Ali: Simply the best

It all started because somebody stole his bicycle in his hometown of Louisville, Kentucky: As boxing coach Joe Martin, who "discovered" the future heavyweight champion, would later recall, the then 12-year-old Cassius Marcellus Clay Jr. ran into his arms in tears one day, pledging to "whup" the thief. Martin took Clay, a black boy from a poor family, under his wing.

Years later, Martin described Muhammad Ali as the hardest-working boxer he ever coached, and while Ali still lacked power in his punches, right from the start he was very agile on his feet.

At 18, Cassius Clay won the gold medal in the light-heavyweight division at the 1960 summer Olympic Games in Rome. In a 1975 autobiography, though, Ali claimed that he threw his gold medal into the Ohio River after an act of discrimination, which he was subjected to shortly after he had returned home. This account has been disputed by a couple of his cohorts at the time.

Clay ended his amateur career with a record of 100 wins from 108 bouts, before moving into professional boxing with the support of 11 white Louisville businessmen.

"I am the greatest!"

From the very start, the extremely talented boxer had a well-earned reputation as an arrogant loudmouth. Before every fight, Clay would boast that he was the greatest of all time and make fun of his upcoming opponent.

He went into is first professional title fight against the then-champion, Sonny Liston, in 1964, as the clear underdog, but after just six rounds, the champ threw in the towel. "I am the greatest," the new world heavyweight champion roared into the microphones.

That same year, the boxer joined Malcolm X's "Nation of Islam" and changed his name to Muhammad Ali. In 1967 he refused to be conscripted into the US Army and was subsequently convicted of draft dodging. Ali remained free on bond but was banned from boxing in the United States. He did, however, continue to fight abroad, facing opponents such as West German prize fighter Karl Mildenberger, Canada's George Chuvalo, and Englishman Henry Cooper. He also used public appearances to rail against the US war in Vietnam

Fight of the century

Hollywood stars Richard Burton and Henry Fonda, along with writer Truman Capote, were among those who campaigned for Ali to be allowed to return to the ring in the United States. In 1971, the US Supreme Court overturned his conviction, ruling that he should have been granted the status of conscientious objector.

His return to the ring came on March 8, 1971, at New York's Madison Square Garden in what became dubbed as the "fight of the century" against the then-world champion, Joe Frazier.

This was not just about boxing for the American public. Due to his political views, Ali was seen as representing American counterculture, while Frazier embodied the establishment. Frazier won the 15-round bout on points, and for the first time in his career, Ali went to the canvas in the 15th round.

Ali shuffle

There were a number of other legendary fights in Ali's career, including the "Rumble in the Jungle" in Zaire (now Democratic Republic of Congo) in 1974. Ali knocked out the previously undefeated champion at the time, George Foreman, who was one of the hardest punchers in the history of the sport. Ali did so by dancing around the ring in something dubbed the "Ali shuffle," striking in the eighth round, after he had tired out his opponent. Ali famously described his style as "float like a butterfly, sting like a bee."

Three-time world champion

The win made Ali the second heavyweight after Floyd Patterson to win back the title after having lost it. He went one better by beating Leon Spinks in 1978 to win back the title for a record third time.

Ali's third and final fight against Joe Frazier is remembered as one of the best in history. In the 1975 bout, dubbed the "Thrilla in Manila" Frazier failed to re-enter the ring for the 15th round, giving Ali the decision by technical knockout.

At age 39, Muhammad Ali retired from boxing in 1981 after having lost his last fight to Jamaican-born Canadian Trevor Berbick.

Parkinson's disease

By this time Ali was already suffering from Parkinson's disease and his health deteriorated rapidly over the next few years. The blows to the head that he had suffered over the course of his career had clearly taken a heavy toll. This was plain for the whole world to see when he struggled with trembling arms to reach out and light the Olympic flame in Atlanta in 1996. At the opening ceremony of the 2012 summer Games in London, although he was no longer physically capable of carrying it, Ali was one of the honorary bearers of the Olympic flag.