Nicola Cortese has stepped down from his position as chairman of Southampton.
The Italian banker was rumoured to have handed in his resignation at the South Coast club amid reports of boardroom unrest.
Owner Katharina Liebherr has named herself as temporary replacement, while it is still unclear whether Mauricio Pochettino will follow the 45-year-old out of the door at St Mary's.
"With great regret we have accepted the resignation of Mr Cortese," read a statement from the club. "He has done a wonderful job and we very much wanted him to stay.
A search has now begun for a successor. It is business as usual and we will ensure that the manager, team and staff at the club have all the help and support they need."
Cortese spearheaded to deal to buy the Saints on behalf of the late Markus Liebherr in 2009.
