Floyd Mayweather, Jr. (born February 24, 1977) is a professional American boxer. His father, Floyd Mayweather Sr.,a former convicted felon, is a former welterweight contender and is currently working as a professional boxing trainer. One of his uncles, Jeff Mayweather, is a former IBO super featherweight champion. Another uncle, former two-division world champion Roger Mayweather, is Mayweather Jr.'s current trainer. Mayweather Jr. has started his own record label called Philthy Rich Records.
Mayweather had a successful amateur career with a record of 84-6. He won national Golden Gloves championships in 1993 (at 106 lb), 1994 (at 112 lb), and 1996 (at 125 lb). He was given the nickname "Pretty Boy" by his amateur teammates because his face never had cuts or bruises after fights—a result of the defensive techniques that his father (Floyd Mayweather Sr.) and uncle (Roger Mayweather) had taught him. In his orthodox defensive stance, Mayweather—much like James Toney—often utilizes the 'shoulder roll.' The shoulder roll is an old-school boxing technique in which the right hand is held normally or slightly higher than normal, the left hand is down around the midsection, and the lead shoulder is raised high on the cheek in order to cover the chin and block punches. The right hand (from orthodox stance) is used as it normally would be to block punches coming from the other side, such as left hooks. From this stance, Mayweather blocks, slips, and deflects most of his opponents' punches, even when cornered, by twisting left and right to the rhythm of their punches.

At the 1996 Olympics in Atlanta, Mayweather won a bronze medal by reaching the finals of the featherweight (57 kg) division's 31-boxer tournament. In the opening round, Mayweather led 10-1 on points over Bakhtiyar Tileganov of Kazakhstan before he won by round 2 referee stoppage. In the second round, Mayweather outpointed Artur Gevorgyan of Armenia 16-3. In the quarterfinals, Mayweather survived a late rally by Lorenzo Aragon of Cuba to win 47-11. In his semifinal bout against the eventual silver medalist, Serafim Todorov of Bulgaria, Mayweather lost by a controversial decision that the U.S. team officially protested. Many who saw the bout, including the referee, (who mistakenly raised Mayweather's hand when the decision was read) believed that Mayweather had won.
Mayweather fought his first professional bout on October 11, 1996 against fellow newcomer Roberto Apodaca. Apodaca was knocked-out in round 2. Mayweather's trainer at the time was his uncle, Roger Mayweather, because Floyd Mayweather Sr. was still imprisoned after having been convicted of illegal drug trafficking in 1993. Mayweather Sr. took over as Mayweather Jr.'s trainer when he was released from prison (after Mayweather Jr.'s fourteenth fight—a second round knockout of Sam Girard). From 1996 to early 1998, Mayweather fought against relatively easy opponents and won most of the fights by knockout or TKO. The most notable of these fights was a unanimous decision victory over former IBO lightweight champion Tony Pep on June 14, 1998.

In 1998, Mayweather won his first world title, the WBC junior lightweight (130 lb) championship, when the corner of Genaro Hernandez stopped the fight after round 8. Hernandez had never been defeated at the weight class. From there, Mayweather defended his title with performances against contenders such as Angel Manfredy and Carlos Gerena. Mayweather was named as The Ring magazine's fighter of the year for 1998.

Before he fought against former WBC featherweight champion Gregorio Vargas in early 2000, Mayweather fired his father as his manager and replaced him with James Prince. A few months after the fight, the rift between the father and son became wide enough that Mayweather Jr. fired Mayweather Sr. as his trainer as well. Roger Mayweather returned to his role as Mayweather Jr.'s trainer in his next bout—a non-title fight against Emanuel Burton. In an interview in 2004, Mayweather Jr. said that he loves Mayweather Sr. as his father but feels that he has better chemistry with Roger, and his father had put too much pressure on him to be perfect. On a May 7 appearance on the "Tonight Show", Mayweather stated that his father "just needs a hug" and that "everyone should just hug his father".

Mayweather's biggest fight as a junior lightweight was on January 20, 2001, against Diego Corrales. At the time, neither fighter had been defeated or knocked down. In the bout, Mayweather won every round and knocked down Corrales five times (three times in round 7 and twice in round 10). After the fifth knockdown, Corrales' cornermen climbed onto the apron and stopped the fight, thereby establishing Mayweather as one of the claimants to boxing's mythical pound-for-pound title. At the time of the stoppage, Mayweather was wide ahead on the scorecards, leading by the official tallies of 89-79, 90-79, and 90-78.
In Mayweather's next bout, on May 26, 2001, future IBF champion Carlos 'Famoso' Hernández knocked down Mayweather for the first time. Mayweather entered the bout with injured hands. When Mayweather hit Hernández with a left hook in round 6, the pain caused Mayweather to drop his left hand to the canvas, and the referee called it a knockdown. Nonetheless, Mayweather won the fight by unanimous decision. In the award-winning documentary film More Than Famous, Hernández's bout against Mayweather was prominently featured.

Mayweather's last fight in the junior lightweight division was against future junior lightweight and lightweight champion Jesús Chávez. It was Mayweather's eighth defense of the WBC junior lightweight title, which he had held for more than three years. He won when Chávez's corner stopped the fight after round 9. Mayweather had such difficulty making weight for this fight that he did not eat for four days before the weigh-in.[