Former Sunderland manager Simon Grayson has suggested that replacement Chris Coleman will not be able to change the club's fortunes "overnight".
Last month, Grayson was sacked after winning just three of his first 18 games since moving to the North-East outfit in June, and the Black Cats have moved to bring in Coleman after his resignation as Wales coach.
However, Grayson has claimed that the club's hierarchy must be patient with Coleman if they ever want to secure a return to the Premier League.
The 47-year-old told BBC Radio 5 live: "I suffered the consequences of not winning enough matches and not being given enough time to turn it around. "I had no disbelief with the group of the players that I had that we wouldn't be able to turn it around, and I'm sure Chris will be thinking the same thing.
"I think the biggest thing Chris will need is time because it does not happen overnight. You can't turn a club around so quickly when it's been through some real dark stages, and that's what he will need to make it a success again."
Sunderland currently sit at the bottom of the Championship standings.
