Floyd Mayweather Jr has called 50 Cent's attempts to publicly ridicule the boxer's alleged inability to read as "tragic".
The rapper, real name Curtis Jackson, recently published a video on Instagram challenging the unbeaten fighter to read a page from a Harry Potter book, before asking Mayweather to narrate an extract from Green Eggs and Ham by Dr Seuss.
The Independent quotes Mayweather as saying: "Making fun out of a person because he can't read is not funny – it is tragic.
"I would be perfect at reading if it was how I made my living and fed my family. I'm a boxer, that's what I do and I will say this - intelligence and education are two totally different things."
Mayweather will collide with Marcos Maidana at the MGM Grand in Las Vegas this weekend.