Floyd Mayweather is asked about a lot of fighters. He can't possibly be expected to know them all, but it helps when you at least get their gender right -- especially when you're talking about Ronda Rousey, one of the most recognizable names in the fighting world.
Mayweather sat down with BoxingScene.com to record a video about his next potential opponents when Rousey's name was mentioned. She's currently the UFC Bantamweight Champion and one of the most dominant fighters in the world. UFC Commissioner Dana White said Rousey could beat Mayweather, prompting Boxing Scene to ask the question. Floyd's response?
"Actually, I don't even know who he is."
Hanging out with Justin Beiber too much will damage your memory and general knowledge like that.
h/t The Big Lead