Brighton are set to up their offer for Paddy McNair this week, with Sunderland facing an increasing battle to hold on to their star midfielder.
Premier League Seagulls have had two bids rejected so far, the latest for £3.5million, while an unnamed London-based club has seen an offer of £3.75million knocked back.
McNair has not indicated he wants to leave Sunderland, though he has spoken of a desire to play Premier League football again.
It comes as Stewart Donald has warned those players that have expressed a desire to leave that they won’t do so on the cheap.
Reports in Turkey claimed the agents of wantaway duo Wahbi Khazri and Lamine Kone had attempted to get the duo free transfers this summer following the Black Cats’ relegation to League One.
But Donald has made it very clear Sunderland’s new owners won’t be taken for a ride and will demand market value for any player wanting to leave.
Sunderland have an interest in Hibernian central midfielder Dylan McGeouch, a free agent this summer, and former Gateshead winger Marcus Maddison after Peterborough United missed out on promotion
Maddison has a verbal agreement with Posh chairman Darragh MacAnthony that he would be allowed to leave if they failed to win promotion last term, though there is strong interest in him from several Championship clubs.
Burton Albion defender Tom Naylor, who can also play in midfield, is also reported to be on Sunderland’s wanted list.
Naylor is out of contract at the Brewers but has been offered a new deal and is weighing up his options.
New manager Jack Ross is expecting a high turnover of players at Sunderland this summer.
McNair ended the season strongly with four goals in his last five games and it is no surprise to see the ex-Manchester United midfielder in demand.
The 23-year-old is currently away on Northern Ireland duty and has spoken of his ambition to one day play again in the top flight.
McNair said: “I love playing for Michael [O’Neill, the national team boss] because he gives me so much confidence. I’ve learned a lot off him since I first came into the squad and I think I’ve definitely improved.
“If I can get back to the Premier League, that would be great, but I just want to concentrate on these Northern Ireland games and look at that afterwards.”