Neal Ardley has been sacked by Wimbledon with the League One club floundering in the relegation zone.
He was the third longest-serving current manager in the Football League. Eddie Howe has now taken over third position and has been in charge of Bournemouth for six years and 30 days.
Morcambe boss Jim Bentley is in top spot having been in his role for seven years and 183 days.
Ardley had been at the helm since October 10, 2012 and sparked a turnaround in fortunes for the Dons but this season hasn't gone to plan and the team lie just one point above basement boys Bradford City.
The 46-year-old has left along with assistant manager Neil Cox. First-team coach Simon Bassey has been placed in temporary charge.
Ardley helped the club fight out of relegation from the Football League when he took over and subsequently led the team to a League Two play-off win.
Chief executive Erik Samuelson told the club's website: 'Neal has been a credit to the club in everything he has done. He is a clear thinker, a superb man-manager and a fine coach.
'I've enjoyed working with him and am absolutely certain that he will achieve even greater success in his next roles.
'So, he leaves with my personal thanks and gratitude for what he has done in his time here at AFC Wimbledon.
'I also want to register the club's and my personal thanks to Neil Cox who has provided massive support to Neal throughout his time here and has been a great ambassador for the club. We wish him well in his future career.'
