Hertha Berlin are reportedly holding out for £8.5million each to part with star players Gojko Kacar and Adrian Ramos.
The club have flatly denied rumours that Serbia midfielder Kacar is to leave, with Serie A side Sampdoria rumoured to be interested.
The 23-year-old had been one of the German club's stand-out performers this season despite their relegation from the Bundesliga, and they will look to receive a significant offer before parting with him.
Kacar was part of the Serbian side that finished bottom of their group in the World Cup and came on against Germany as a substitute in their 1-0 victory.
Hertha are rumoured to be looking for a fee of around £8.5million, with Kacar already reportedly ready to leave after agreeing personal terms with either Sampdoria or to stay in Germany with Hamburg.
"Gojko Kacar is a player of Hertha Berlin and has a contract going on at our club," general manager Michael Preetz told Bild.
"We have thus far not received any concrete offer in his respect, though at this point of time he is not going to move on to any club."
Hertha may also have to part ways with striker Ramos despite their reluctance after his agent claimed he was unwilling to play in Germany's second tier.
Ramos, who finished top scorer for the club after joining from Colombian side America de Cali for £1million last season ,was reported to be interesting Hoffenheim, however they have baulked at Hertha's £8.5million asking price.
"Adrian is unhappy, he is anything but motivated. This is leading me to the issue whether it is really a good idea to keep a player that is just forced to stay on," said the Colombian forward's agent Helmut Wennin.
"The issue is that Adrian is unwilling to play in the second tier and I want Hertha Berlin to understand."
Hoffenheim general manager Ernst Tanner stated that the club were interested in the player, but the figure was too high for them to pay.
"He is an interesting player," said Tanner.
"But this is a figure we do not even need to mention. Any deal is off from our point of view due to this."