Brendan Rodgers has quit as Celtic manager, a club statement has confirmed.
The Northern Irishman, who led the club to four Scottish Premiership titles over two spells, has departed the club following the 3-1 defeat to league leaders Heart of Midlothian with the reigning champions trailing the capital side by eight points.
Former manager Martin O'Neill and ex-player Shaun Maloney will take over the first team as the club search for a new manager.
Celtic face Falkirk in the William Hill Premiership on Wednesday before facing Rangers at Hampden in Sunday's Premier Sports Cup semi-final.
A Celtic statement said: "Celtic Football Club can confirm that football manager Brendan Rodgers has today tendered his resignation. It has been accepted by the Club and Brendan will leave his role with immediate effect.
"The Club appreciates Brendan’s contribution to Celtic during his two very successful periods at the Club.
"Brendan leaves Celtic with our thanks for the role he has played during a period of continued success for the Club and we wish him further success in the future.
"The process to appoint a new permanent manager is underway and the Club will update supporters further on this as soon as possible.
"We are pleased that during this interim period former Celtic manager, Martin O’Neill and former Celtic player, Shaun Maloney have agreed to take charge of Celtic first-team matters."