Millwall boss Nigel Spackman has left the League One club by mutual consent following a disappointing start to the season at The Den.
The Lions are second bottom of the table after just one win and two draws in their opening ten games, while they were dumped out of the Carling Cup second round with a thumping 4-0 home defeat against Southampton last week.
Following Saturday's 1-0 home reverse against Northampton Spackman, who took over the job in the summer, and the club have decided to part company.
Assistant boss Willie Donachie will remain in caretaker charge while a new manager is found.
Lions chairman Stewart Till told the club's official website: "This has been a very difficult decision for both parties. We firmly believed that Nigel was the manager to take us back to the Championship.
"His qualities as a man and his vision for Millwall's future were impeccable, but unfortunately circumstances have dictated that things have not worked out as either he or we anticipated in the first ten games of the season.
"For a club of Millwall's size and ambitions clearly this has been a cause for concern, and consequently the Board have concluded, after discussion with Nigel, that we must seek a different approach. We thank Nigel for all his professionalism and hard work."
Spackman added: "Naturally I am very disappointed that results have not gone for us so far this season. I am still convinced that in time the squad of players at Millwall are capable of turning things around and moving up the table.
"In my short time at The Den, I very much enjoyed my association with Millwall and I wish the club all the very best for the future.
"As I stated on a number of occasions, this is a results based business, and time is not on the manager's side when results are not going your way."