5 – Floyd Mayweather Jr.
Floyd Joy Mayweather Jr. is an American boxing promoter and former professional boxer who competed between 1996 and 2017. He retired with an undefeated record and won 15 major world championships from super featherweight to light middleweight. This includes the Ring magazine title in Five weight classes and the lineal championship in four weight classes (twice at welterweight). As an amateur, he won a bronze medal in the featherweight division at the 1996 Olympics, three U.S. Golden Gloves championships (at light flyweight, flyweight, and featherweight), and the U.S. national championship at featherweight.
Floyd Mayweather Jr.
4 – Rocky Marciano
Rocco Francis Marchegiano (September 1, 1923 – August 31, 1969; Italian, better known as Rocky Marciano, was an Amerian professional boxer who competed from 1947 to 1955. He held the world heavyweight championship from 1952 to 1956, and remains the only heavyweight champion to finish his career undefeated. His six title defense were against Jersey Joe Walcott (from whom had taken the title), Roland La Starza, Ezzard Charles (twice), Don Cockell and Archie Morre.
Rocky Marciano
3 – Sugar Ray Robinson
Walker Smith Jr. (May 3, 1921 – April 12, 1989), better known as Sugar Ray Robinson, was an American professional boxer who competed from 1940 to 1965. He was inducted into the International Boxing Hall of Fame in 1990. He is often regarded as the greatest boxer of all time, pound-for-pound.
Robinson held the world welterweight title from 1946 to 1951, and won the world middleweight title in the latter year. He retired in 1952, only to come back two-and-a-half years later and regain the middleweight title in 1955.
Sugar Ray Robinson
2 – Joe Louis
Joseph Louis Barrow (May 13, 1914 – April 12, 1981) was an American professional boxer who competed from 1934 to 1951. Nicknamed "the Brown Bomber", Louis is widely regarded as one of the greatest and most influential boxers of all time. He reigned as the world heavyweight champion from 1937 until his temporary retirement in 1949. He was victorious in 25 consecutive title defenses, a record for all weight classes. Louis had the longest single reign as champion of any boxer in history.
Joseph Louis Barrow
1 – Muhammad Ali
Muhammad Ali (born Cassius Marcellus Clay Jr., January 17, 1942 – June 3, 2016) was an American professional boxer and activist. Nicknamed "the Greatest", he is regarded as one of the most significant sports figures of the 20th century and is often regarded as the greatest heavyweight boxer of all time. He held the Ring magazine heavyweight title from 1964 to 1970. He was the undisputed champion from 1974 to 1978 and the WBA and Ring heavyweight champion from 1978 to 1979. In 1999, he was named Sportsman of the Century by Sports Illustrated and the Sports Personality of the Century by the BBC
Muhammad Ali
He fought in several historic boxing matches, including his highly publicized fights with Sonny Liston, Joe Frazier (including the Fight of the Century, the biggest boxing event up until then), the Thrilla in Manila, and his fight with George Foreman in The Rumble in the Jungle. Ali thrived in the spotlight at a time when many boxers let their managers do the talking, and he became renowned for his provocative and outlandish persona. He was famous for trash-talking, often free-styled with rhyme schemes and spoken word poetry, and has been recognized as a pioneer in hip hop. He often predicted in which round he would knock out his opponent
