Roy Keane has told the Sunderland board to take a "good look at themselves" following Dick Advocaat's decision to resign as head coach over the weekend.
The Dutchman opted to walk away from the Black Cats just eight games into the Premier League season.
Keane spent 27 months in charge of the North-East team before leaving in December 2008 after falling out with owner and chairman Ellis Short.
When asked by reporters if he was surprised by Advocaat's resignation, Keane said: "No. It's Sunderland, isn't it? It's a brilliant club but, I don't know, I really can't comment on why different managers have left or have been sacked, but people in the background probably need to have a good look at themselves."
When asked if he was referring to people who were working at the club during his spell in charge, Keane said: "Yes. If they'd left me alone, I'd probably still be there now and I wouldn't be having to chat to you."
Keane now works as assistant coach to Martin O'Neill for the Republic of Ireland national team.