Ian Holloway has been fired as manager of Millwall following a disastrous run of results.
Coach Neil Harris has been given the reins for the remainder of the season as the Lions battle the threat of relegation.
In a statement released on Tuesday morning, chairman John Berylson said: "This was a hard decision to take because we very much hoped that Ollie would prove to be the man to take us forward and on to the next level.
"I would like to thank him for his efforts, and in particular for keeping us in the Championship last May.
"This season, though, has proved to be an extremely challenging one and we now find ourselves facing another uphill battle to avoid relegation.
"Ian Holloway remains a fine manager and it was his impressive track record which led us to appoint him some 14 months ago.
"However, our view is that the decision to part company at this stage is in the best interests of the football club going forward."
Millwall are currently second from bottom, eight points from safety with just 10 games remaining this season.
The south Londoners have lost their last four games and have not won at The Den since October.