Phil Parkinson and his coaching staff were today sacked by Charlton's new owners.
The decision, announced on the club's official website, comes after the 4-2 defeat at home to Swindon yesterday and the npower League One club will announce the appointment of a caretaker manager "in due course".
Following the takeover of the club last week, new chairman Michael Slater had stated he would back Parkinson in the January transfer window and give him every support.
Slater has now backtracked on his comments, confirming the departure of Parkinson, assistant manager Tim Breacker and first-team coach Mark Kinsella.
"Clearly improvement is needed on the field. The team has not won in the league since November and recent performances have simply not been good enough," he said.
"Last night's defeat convinced us as a board that change is required now while we are still in the hunt for promotion, and that we must appoint a new manager to give us every chance of going up."
Parkinson was appointed at The Valley in 2008 and leaves the Addicks in fifth place of League One, just three points off the automatic promotion places.