Former Sunderland manager Paolo Di Canio has hit out at Martin O'Neill for calling him a "charlatan".
The Italian replaced O'Neill as the Black Cats boss in March and helped the club retain their Premier League status, but was sacked in September following a disappointing start to this season's campaign.
"I don't know if he knows the meaning of this word charlatan," he told Sky Sports News. "Probably I can teach him, even if I am not English.
"I respect the opinion of manager Martin O'Neill but the fact that he spoke after six months, not straight away proves what kind of level he is. He is not very big.
"A charlatan is a manager who spends £40m to be a top 10 club and then sees the club sink into the relegation zone."
Gus Poyet succeeded Di Canio as the Sunderland boss.
