Sam Allardyce believes the only way Sunderland can get back on track is with a new owner.
The former Black Cats boss has given a revealing interview about his time on Wearside, owner Ellis Short, and how he believed David Moyes would kick the club on from his success in saving it from relegation.
Allardyce's brief spell in charge of Sunderland ended in July 2016 when he left to take over as England boss, having guided the club to Premier League safety after taking 12 points out of a possible 18 at the end of the campaign.
Since his departure, Sunderland have won just seven out of 54 league games, sliding out of the top flight and now finding themselves bottom of the Championship looking for their eighth permanent manager in five years.
Allardyce believes owner Short - who tried to sell the club in the summer - must has to leave if the Black Cats are to prosper in the future.
He said: "To get Sunderland back into a fit state, the club needs to be sold.
"I think Ellis Short was fine while I was there, but it’s obvious he’s had enough. He’s pumped so much money into the club and I don’t believe he wants to risk any more of his cash.
"They find themselves at the wrong end of the Championship table, they’ve sacked another manager – Simon Grayson – but the rot had set in at Sunderland and it’s very difficult to manage a club when they’re in that position. It’s even harder to overcome it and get a team back into the right direction.
"So maybe, at this stage, a new owner is what’s left to change and should get them back on the right track at this period in the club’s history."
Allardyce believes the club would be in a lot healthier position if he was still at the Stadium of Light, calling the situation 'tragic'.
And he has revealed that before he quit to become England boss, he tried to persuade Short that more investment was needed - and that he felt he'd left the club in safe hands under his successor Moyes.
"It’s so tragic what’s going on at Sunderland at the minute," added Allardyce. "Especially for me, thinking that I left that club after saving them from a relegation fight.
"The fight for me in my time at the club was trying to convince the owner this really couldn’t happen again.
"It was the fifth time they’d been in that position and, in my experience over many, many years as a manager, it was me trying to say that a relegation fight shouldn’t be happening again. But before I got the chance to put that into action, I’d obviously left.
"Honestly, when David Moyes came in after me, I genuinely thought he could carry it on. He’s a good friend of mine and a great manager.
"But, unfortunately, right from when he came in, things didn’t go well. Sunderland have never recovered from that."
The Black Cats now find themselves in another relegation dogfight, this time with the spectre of League One football looming over them.
Allardyce says the players will be 'mentally scarred' after last season and admits it could be 'impossible' for the club to reverse the decline in the immediate future.
"The way they’re going at the minute, they’re dangerously close to being relegated again," the 63-year-old said.
"When you saw what Simon did with Preston North End, and on a very limited budget, it was obviously good business by the owner to bring him in. He showed at Preston that he was more than capable of working on very little funds and still having success with a team.
"Unfortunately, the fall-out of being relegated, which I experienced at West Ham, leaves the club in a very difficult position. Those lads will be scarred mentally, they’ll obviously want to leave and there’s cut backs, redundancies and sackings which follow.
"That’s tough on everyone, and it makes it almost impossible to get the right mood and spirit back into the club. I’m not sure how they’ll do it, but I really hope they do."
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