1:55PM BST 15 Jun 2011
Sunderland reacted swiftly to claims that the 25-year-old Ghana international's name has been circulated to prospective purchasers.
In a statement, Quinn 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."
A report suggested Gyan was being put up for sale to help fund a summer spending spree.
His situation has been in the spotlight for several weeks amid reports that Tottenham could be ready to test Sunderland's resolve to hang on to him this summer.