But the Eagles chief insists their friendship will be put to one side when he attempts to steer the south Londoners into the fifth round of the competition at Molineux.
Warnock told the South London Press: "Not a lot of people know that we know each other. Mick used to clean my boots at Barnsley, which stood him in good stead.
"Mick always talked sense about the game and is level-headed and a natural leader. I'm not surprised to see what he has done in his life. He's doing brilliant with Wolves.
"The first time he went up with Sunderland he didn't have a chance of staying there but Mick has learned from that. One or two decisions have upset people but he is just geared to keeping them up. They have got a good chance of doing that."