Feyenoord chief Martin van Geel is bracing for offers to arrive for defender Stefan Vrij.
Aston Villa, Everton and Newcastle United have been linked with the 20 year-old.
Van Geel told RTV Rijnmond: "Nobody has yet been in touch over De Vrij.
"You never know. There will always be rumours. Until September 1st the transfer window is open and the unrest will undoubtedly continue."