American businessman Mark Campbell is in line to become the new majority shareholder of Sunderland, taking a 74 per cent stake in the club.

Sportsmail can reveal that the deal would see Campbell acquire 64 per cent from owner Stewart Donald and 10 per cent from Uruguayan investor Juan Sartori.

That would leave Donald and Sartori each with a 10 per cent stake, and executive director Charlie Methven is likely to retain the six per cent share he was given by Donald for brokering the purchase of the club from Ellis Short just 13 months ago.

Sunderland owner Stewart Donald is set to sell 64 per cent of his stake in the League One club

Campbell has undertaken due diligence and it is expected that the deal will go through before the end of month.

Manager Jack Ross, whose side were beaten by Charlton in the League One play-off final, will stay, and former Celtic scout John Park will arrive as director of football.

Sunderland insist they are still talking to other parties, but sources have indicated that Campbell is the only serious contender left to take control. The stockbroker was sitting next to the current chairman at Wembley last weekend.

Methven told Sportsmail: 'We expect a resolution or some clarity before the end of June and in time for pre-season.

Juan Sartori (left) with fellow director Charlie Methven (right) will retain shares in the club

'It is a case of re-examining the situation and asking, "Is it the right deal at the right time?" We have to consider what we think is best for the club in the short, medium and long term.

'Stewart has said that he is in discussions with a number of potential investors, and three or four of those are still in play.

'No share purchase agreement has yet been signed, and were it going to be a new majority shareholder, they would still need to go through the EFL approval process.

'So it remains a possibility that Stewart will stay in control and nothing will change. The necessity for investment is no longer there because we will still be in League One next season.'

Donald purchased his shares in the Wearside club just 13 months ago

The value of the deal is unknown, given that talks began before failure to gain promotion, but it is understood that a figure of £50million for a full takeover had been mooted. It is also unclear what position Donald, who is currently chairman, will hold.

Donald bought the club for around £37m just over a year ago. He has since confirmed that a chunk of the club's Premier League parachute payments were used to complete that deal.

It is not known if any of that outstanding money will be paid back to the club should Donald sell the majority of his stake.

Campbell is said to be heading a New York-based consortium with links to the Far East.