The South African is currently plying his trade for the Orlando Pirates, and reminiced his time with the Portuguese with A BOLA, as the duo lifted the UEFA Champions League trophy in 2003-04.
"He really is special. He gives everyone a tactical lesson and I do not believe in the next 100 years there will be anyone like him", the 33-year-old lauded.
"He has charisma, style, he is smart and especially a good friend. You know those papers he used to give us during the games? Most of them read 'you have 10 minutes to score a goal'.
"Mourinho is amazing."
McCarthy also revealed he was close to signing for Sporting Lisbon in 2010.
"Costinha, who was then the club's director, spoke to me and we almost came close to an understanding, but the transfer fell through," McCarthy said.
"It was a shame, because I really wanted to return to Portugal", he concluded.