Jose Luis Castillo vs. Floyd Mayweather Jr. (1st meeting)
2002-04-20 : Floyd Mayweather Jr 134 lbs beat Jose Luis Castillo 134½ lbs by UD in round 12 of 12
- Location: MGM Grand, Las Vegas, Nevada, USA
- Referee: Vic Drakulich
- Judge: Anek Hongtongkam 116-111
- Judge: John Keane 115-111
- Judge: Jerry Roth 115-111
- World Boxing Council Lightweight Title (4th defending of Castillo)
- Weights: Castillo 134.5 lbs, Mayweather 134 lbs
- Mayweather wins the vacant Ring Magazine Lightweight championship of the world.
- Mayweather won early rounds with his jab by keeping the fight outside.
- Castillo won late rounds as he outworked Mayweather on the inside, especially to the body.
- Castillo was penalized in the eighth round for hitting on the break.
- Mayweather was penalized in the tenth round for elbowing.
- HBO's unofficial scorer Harold Lederman had Castillo winning 115-111.
- See also: Mayweather vs. Castillo II.