Floyd Joy Mayweather Sr. (born October 19, 1952) is an American boxing trainer and former professional boxer who competed from 1973 to 1990.

He has on many occasions, including HBO's Mayweather-Hatton 24/7, claimed to be Floyd Mayweather Sr., 'The Greatest Dog of All Time'".

After considerable deliberation, De La Hoya opted not to hire Mayweather Sr. and announced on January 30, 2007, he would use Freddie Roach instead.

The snub briefly reunited father and son,[5] with Floyd Sr. turning up at the Mayweather Jr. boxing gym, while Roger (who had been banned from being in the corner at boxing matches for 12 months for starting a riot during Floyd Jr.'s bout against Zab Judah on April 8, 2006, when he attacked Judah) served six months in jail for a domestic assault.

Mayweather Sr. trained Manchester's Ricky Hatton for seven weeks prior to his bout against Paulie Malignaggi on November 22, 2008, at the MGM Grand in Las Vegas.

While some speculated this was because of the bloody nose Jr. got in an otherwise dominant performance against Miguel Cotto (a change to the more defensive-oriented Floyd Sr. over the offensive Roger was seen as logical), Floyd Jr. cited his uncle Roger's health issues, diabetes, and poor vision as rationale for the change.