Chesterfield have parted ways with manager Martin Allen, after a 4-0 defeat by Solihull Moors.
His backroom staff; assistant manager Adrian Whitbread and goalkeeping coach Carl Muggleton, have also left the club.
John Pemberton, who runs the club's academy, is now in caretaker charge.
CEO Graham Bean said: “On behalf of the club, I would like to thank Martin and his staff for their hard work and wish them all the very best for the future. The search for a new manager is now underway."
Allen was appointed in May by club owner Dave Allen, who said at the time: “He’s the right man at the right time for this job, make no mistake about it.”
A PR blitz helped the former Barnet and Brentford boss to get fans onside over the summer and optimism was rife after a pair of relegations on the trot.
And indeed they began the season well, winning their first three games.
But they went 19 National League games without a victory before 8th December's win over Salford City.
Since then they'be beaten Basford in the FA Trophy and lost at leaders Leyton Orient.
On Saturday, at home to Solihull they made a nightmare start, conceding after just four minutes.
Allen dragged centre-half Michael Nelson off before the 10 minute mark, but Nathan Blissett - a Spireites summer transfer target - went on to grab his and Solihull's second before half an hour was played.
When Moors' third goal went in, a group of Chesterfield fans invaded the pitch to protest and the game was halted for eight minutes.
Solihull scored a fourth shortly after things resumed.
Allen has been the subject of angry chants from fans, a couple of hundred of whom attended a recent protest over the running of the club and it's decline from a League One promotion hopeful to a National League struggler.
His 30 games in charge yielded seven wins, 12 draws and 11 defeats.
The Spireites are now looking for their sixth permanent manager since Paul Cook departed in May 2015.
Earlier today, director Ashley Carson resigned from the board and according to CEO Graham Bean has stepped away from the day to day running of the club.