The former Uruguay international told the team's website: "I spoke to Kevin shortly and we're going to have a longer meeting soon but I know how important he is to the club.
"He doesn't know yet, how important he is going to be for me. The people who are already at the club they know how it works, they know the players, the staff, what the fans like, things that a new manager needs to know.
"It's clear that you need someone with the qualities of Kevin in here so I'm going to count on him a lot. I think we both believe that this is a club, this is Sunderland, so we will both make sure that we do the best for the club."
Sunderland return to league action at home to Swansea City on October 19.