Jonathan Morgan has left his position as manager of Leicester City after seven years in charge.
He guided the club to the Women's Super League for the first time last season after they won the Championship title.
Leicester currently sit bottom of the WSL table after eight games having not picked up a single point.
Morgan, who signed a new contract in July, was named LMA Championship Manager of the Year following Leicester's success last season.
"This club has been part of mine and my family's life for 12 years from when my sister Holly Morgan joined as a young player," said Morgan.
"To have taken Leicester from the Midlands Division 1 to an FA WSL club gives me nothing but pride. This season has been disappointing, with injuries contributing to a difficult start, but we haven't achieved the results we had hoped for."
Assistant manager Michael Makoni and first-team coach Holly Morgan - previously club captain - have also left their positions.
Emile Heskey, Leicester's head of women's football development, will oversee first-team training in preparation for Sunday's game against Manchester United in the League Cup.
A club statement said they are "undertaking the process of appointing a new manager".
"Retention of its WSL status is central to the club's vision for the long-term development of women's football in the city," the statement added.
"The club feels a change in leadership is now necessary to give the team the best possible chance of achieving this in the remaining months of the season."
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