Mauricio Pochettino has demanded Chelsea keep hold of Mason Mount.
The England midfielder has a year left on his deal and talks over a new arrangement have collapsed.
Football.London says during the interview process at least two managerial candidates, including Pochettino, demanded Mount be kept on.
But with co-owners Todd Boehly and Behdad Eghbali leaving football duties to co-sporting directors Lawrence Stewart and Paul Winstanley, negotiations have now fallen through and Mount appears set to be sold.
Manchester United are in contact with Mount's camp, along with Arsenal, Liverpool and Newcastle.