Ji Dong-Won, a South Korean international forward, is expected to sign for the Black Cats in the next few days, where he would be expected to join Asamoah Gyan and Fraizer Campbell as the only recognised strikers on the books.
But the club moved yesterday to deny a story published on Tuesday night suggesting that agents had circulated an email to top Premier League clubs inviting bids for Gyan.
The article in a national newspaper implied that the club would be prepared to do business in order to free up transfer funds.
Chairman Niall Quinn, however, said: The suggestion that we have spoken to an agent to sell this player on our behalf is embarrassing to all concerned.
"I hope our fans would be smart enough to realise that this is probably some other club or outside agent's way of attempting to destabilise our relationship with one of our players.''
Gyan, who scored 11 goals in his first season on Wearside, has been linked with a move to Tottenham after manager Harry Redknapp admitted his interest in the Ghanaian striker.
The player has been on international duty recently, scoring against South Korea last week.
The Black Cats return to training on July 6, by which time they expect to have Dong-Won and goalkeeper Kieren Westwood in their ranks, and they will hope to retain the services of Gyan.
Sunderland have agreed a deal around 800,000 for Dong-Won with K-League club Chunnam Dragons, who will get first refusal on him should his time in England not work out.
He will become the first ever South Korean to sign for Sunderland, while at 20 will be the youngest in the Premier League.
Like Gyan, he scored in South Korea last week and, at 6ft 1 is considered one of the taller strikers among Asian players.
Born on the island of Chujado, Dong-Won had a trial at Reading in 2007-08, but has spent the last two years playing in Koreas K-League for Chunnam, where he scored ten goals in two seasons.
While he is predominantly considered a striker, Dragons employed Dong-Won as an attacking midfielder, while he started on the left side of midfield for his country against the Black Stars last week, a position vacated by Ji Sung Park after his international retirement.
Crucially, Dong-Won was brought to the attention of manager Bruce during the Asia Cup, where he scored four goals playing at the head of a 4-3-3 formation.
He is expected to be selected for South Koreas under-23 Olympics squad next summer.