Chesterfield and Martin Allen have this afternoon parted company.
The club are third from bottom of the National League and on Boxing Day lost 4-0 at home to Solihull Moors.
They have won just one league game since the second Saturday of the season.
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.”
Academy manager John Pemberton will take charge of the team for Saturday’s game at home to Hartlepool United.
Allen said after the defeat to the Moors yesterday that standards weren’t being met.
“I thought it was a very disappointing afternoon all-round,” he told the club’s website. “The first ten minutes, I thought our performance from defending set-plays, long balls, direct balls was appalling.
“Then every time they went forward, I thought they were going to score.
“It was an opportunity for some players coming into the team, who hadn’t been playing.
“I was expecting and hoping that they would come in and keep to the same standards that we had been playing to. But the standards were nowhere near it,” the former Barnet manager added.
“The players have got to stand up and be counted, you’ve got to man up and deal with it and face it.”
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