It has been revealed that Sunderland know the price they must meet to land Panathinaikos winger Charis Mavrias.
The Mirror reported that Sunderland must go back in with a £2.5million cash offer for the 19 year old if they still want the Panathinaikos winger.
The Black Cats agreed the fee for the Greece international last month, but attempts to advance the deal were frustrated.