In his prime, as a six-time world champion boxer, Sugar Ray Robinson (1921-1989), was virtually unbeatable in the ring. He reigned as the undefeated world welterweight champion from Dec. 20, 1946, until Feb. 14, 1951, when he won the world middleweight title for the first of five times.

His portrait appeared on the cover of the June 25, 1951, issue of TIME magazine -- the caption read "Sugar Ray Robinson: Rhythm in his feet and pleasure in his work." In 1967 he was elected to the Boxing Hall of Fame. The former editor of The Ring magazine ranked Robinson No. 1 in his 1984 book "The 100 Greatest Boxers of All Time." He was inducted into the International Boxing Hall of Fame in 1990, and nine years later a panel of experts assembled by the Associated Press named Sugar Ray Robinson the No. 1 "fighter of the century."

Sugar Ray Robinson was born Walker Smith, Jr., on May 3, 1921 -- either in Ailey, GA, (according to his birth certificate) or in Detroit, MI, (according to his autobiography). In 1932 his mother moved with Walker and his two sisters from Detroit to New York City. They settled in Harlem, where Walker's natural talent in the ring was noticed at a local gym. He fought amateur matches using, as the story goes, a borrowed Amateur Athletic Union card that had been issued to a youth named Ray Robinson. Building a reputation for himself under the assumed name (which he would later take as his own), he fought a total of 85 amateur bouts and won them all - 69 by knockout, 40 in the first round. The now legendary moniker "Sugar Ray" was coined by a sportswriter for the youngster who sure was a "sweet fighter." In 1939 he captured the Golden Gloves featherweight title. In 1940, after winning the Golden Gloves lightweight championship, Sugar Ray Robinson became a professional boxer.

Robinson launched his career with a second-round knockout of Joe Echeverria on Oct. 4, 1940, at Madison Square Garden. He also won his next 39 fights (29 by knockout) before experiencing his first loss, to middleweight Jake "The Bull" LaMotta in a 10-round bout on February 5, 1943, in Detroit. Three weeks later he won a 10-round rematch with LaMotta.

On Feb. 14, 1951 -- in a bloody fight that afterward was dubbed boxing's St. Valentine's Day Massacre -- Robinson took the world middleweight championship from Jake LaMotta with a technical knockout in the 13th round. But his July 10, 1951, defeat in London by British fighter Randy Turpin (the second loss of his career) cost him the middleweight title. In their rematch two months later at the Polo Grounds in New York City, he regained the crown with a 10th-round technical knockout. In 1952 he retained the title against Carl "Bobo" Olson and Rocky Graziano. Sugar Ray's third and last fight in 1952 was a challenge for Joey Maxim's light heavyweight title. In an outdoor bout on June 25 at Yankee Stadium, Robinson suffered the only technical knockout of his entire career when he collapsed with heat exhaustion. Although ahead on points, he didn't answer the bell for the 14th round and Maxim was declared the victor.

Sugar Ray announced his retirement from boxing on Dec. 18, 1952, but he returned to the ring at the beginning of 1955. With a second-round knockout of Carl Olson during their Dec. 9, 1955, fight in Chicago, Robinson once again reigned as world middleweight champion. Over the next couple of years he would lose the title twice, regaining it each time in rematches. He knocked out Fullmer in the fifth round of their rematch with a dramatic left hook that is still referred to as the "perfect" punch. But on January 22, 1960, he lost the middleweight title to Paul Pender in a split decision and was unable to regain it in their rematch five months later. He continued to box until retiring for good at the end of 1965. The trophy he received in a ceremony at Madison Square Garden on December 10, 1965, was inscribed "The World's Greatest Fighter."

Robinson later moved to Los Angeles where he worked as an actor, obtaining small roles in a few television shows and movies. He established the Sugar Ray Robinson Youth Foundation in 1969 to help inner-city youngsters develop their skills in sports, fine arts, and performing arts. He died from complications of Alzheimer's disease and diabetes on April 12, 1989.