Peterborough have parted company with manager Keith Alexander after less than eight months.
Alexander took over in May
The decision comes after Posh suffered their sixth straight League Two defeat against Darlington, who themselves were on a run of eight losses.
Assistant coach Tommy Taylor will be in charge for Tuesday's FA Cup replay against Plymouth.
Peterborough made a promising start to the season, going unbeaten in August, before suffering a dramatic slump.
A club statement said: "The club would like to take this opportunity of thanking Keith for all his hard work both on and off the field."
Alexander left Lincoln to take over from Steve Bleasdale in May but despite signing a four-year deal, his reign lasted just just seven-and-a-half months.
Irish businessman Darragh MacAnthony, 30, took over from previous chairman Barry Fry in October and immediately set out ambitious plans to be "knocking on the Premiership door in five years".
Club owner Fry stayed on as director of football with MacAnthony gradually buying the former Birmingham, Barnet and Posh manager out.
But Posh have slipped to 10th in League Two despite spending £800,000 on new players, including Josh Low, George Boyd and Micah Hyde.