Manager Paulo Sergio is leaving Hearts after rejecting the offer of a new contract.
The Clydesdale Bank Premier League club, who Sergio guided to a Scottish Cup triumph last month following a 5-1 victory over local rivals Hibernian in the final, confirmed that talks over a new deal had broken down with the 44-year-old Portuguese.
A Hearts statement read: "Heart of Midlothian FC today (Thursday) announces that it has started the search for a new manager after Paulo Sergio did not agree to the terms proposed to him by the club."
It continued: "The club had been hopeful recent negotiations with Sergio would have a successful conclusion but he has opted not to extend his stay at Tynecastle. The club has now commenced the process of putting a new coaching team in place which is capable of building on the success of the William Hill Scottish Cup victory over Hibs."
Sergio expressed his sadness at departing the Scottish club, and admitted he had no idea what his next career move would be.
He said on www.heartsfc.co.uk: "I deeply regret I will not continue my work at Hearts.
"I appreciate the road the club is now going down and respect what our board is doing. But I cannot accept the offer the club has made me.
"I want to say many thanks to everybody who worked with us, including our board, and special thanks to our supporters.
"I wish the very best to this great football club and I am now just one more Hearts supporter. I would also like to say thank you to all the players, who will be friends for life.
"And as for my future? Only God knows."