Kevin Nolan has been sacked as Notts County manager with the club lying bottom of Sky Bet League Two.
The Magpies have been beaten in each of their last four league games after drawing their campaign opener, with the latest defeat Saturday's 3-1 loss at Lincoln.
They started off the season as favourites for promotion, with Sky Bet now pricing them at 7/2 to go up this season.
A statement on the club's official website on Sunday morning said they had parted company with Nolan, with assistant manager Richard Thomas also being relieved of his duties.
Owner and chairman Alan Hardy said: "This is a decision we've made with the best interests of Notts County at heart.
"While the beginning of our 2018-19 campaign has been bitterly disappointing, the board and I believe results and performances throughout 2018 have not been good enough overall.
"The last eight months have seen us win only eight of our 28 Sky Bet League Two matches, a run which saw us surrender our position in the automatic-promotion places before suffering defeat in the play-off semi-finals.
"Our away form has also been a continuing concern, with only two league victories recorded on the road since the turn of the year.
"Ultimately, a continuation of this form would not allow us to meet our targets for the season and, having conceded 16 goals in our last five matches and being without a win in our last 10 competitive games, we feel now is the time to move forward with a new manager at the helm."
Nolan was appointed in January 2017, becoming County's 23rd permanent manager since October 1, 1997, the most of any club in the top four divisions over the same period.
When the 36-year-old took charge - news announced during a press conference where Hardy was also introduced as the new owner and chairman - the club were 22nd in the fourth tier, a point above the relegation zone, and had lost their last 10 league games.
They ended the season in 16th place, before making the play-offs with a fifth-placed finish in 2017-18.
Hardy added: "Everybody knows of my desire to restore the fortunes of the world's oldest Football League club and I have invested substantial monies to strengthen our playing squad in the summer.
"Our supporters have responded magnificently by turning out in their droves but, unfortunately, their efforts have not been backed up by performances on the pitch.
"This club will nevertheless always owe Kevin a huge debt of gratitude for his work in saving us from relegation from the EFL when I first arrived in January 2017.
"It was a truly remarkable turnaround and we wish him and his team every success in the future."
County said first-team coaches Steve Chettle and Mark Crossley would be taking charge of first-team affairs until a new manager is appointed.