Warnock says the Senegal international gave Jamie Mackie some stick after the player went down with what proved to be a badly broken leg during the game due to a clash with Gael Givet.
Warnock said that the Rovers player taunted Mackie as he lay on the floor after the clash.
"He's broken both bones, his tibia and his fibula, and he's gone to hospital but will travel home with us," said Warnock.
"The lads were furious with El-Hadji Diouf; he (Mackie) had broken his leg and he is calling him all sorts on the pitch.
"There was no need to put the finger up and call him a disgrace and even the Blackburn people were embarrassed.
"I can't abide people like that, I don't know why he wants to take on the world every week.
"For many years I have thought he (Diouf) was the gutter type - I was going to call him a sewer rat but that might be insulting to sewer rats.
"I think he is the lowest of the low and I can't see him being at Blackburn much longer because I can't see Steve Kean putting up with someone like that in the dressing room when he is trying to form a new image for Blackburn.
"I think he will be the first to go and good riddance - I hope he goes abroad because I won't miss watching him. He is a nasty little person."