Stephen Robinson has resigned as manager of Motherwell after stating he has taken the club as far as he could.
The Northern Irishman stepped down after Wednesday's 2-0 home defeat by Kilmarnock left them without a win in nine games and in 10th place in the Scottish Premiership, two points off bottom club Hamilton, who they play on Saturday.
A club statement read: "After Wednesday night's match with Kilmarnock, Stephen approached the board, giving an honest assessment of the current situation. He then stated his desire to leave.
"It is with regret that the board accepted his resignation, having carefully considered his reasons for wanting to leave his post."
Assistant boss Keith Lasley has been placed in interim charge with immediate effect and will take the team for Saturday's Lanarkshire derby.
The club statement added: "Despite the current restrictions, the board will now run a thorough process to identify the right person to take the manager's post.
"This will move at pace, mindful of the busy fixture list and the January transfer window's impending opening."
Robinson first joined the club in early 2015 and was assistant to Ian Baraclough and Mark McGhee before returning from a spell as Oldham boss and succeeding the latter in March 2017.
Robinson said: "I would like to thank everyone at Motherwell FC for their support throughout my time here, both as manager and assistant.
"We have qualified for Europe, reached two cup finals and achieved a third-place finish, on top of developing some wonderful players in my time here.
"We cleared the club's external debt through player sales, cup runs and league positions. The club has numerous assets going forward, and I'm sure that they will have a strong finish to the season with the brilliant coaching staff currently there.
"My goal was always to leave the club in a healthier position. I believe the staff and I have done this.
"I now feel it is the time for someone new to take the club forward as I feel I have taken it as far as I can."
Motherwell chairman Jim McMahon also said: "I thank Stephen for everything he has done for this club.
"Year after year, he delivered upon or exceeded the targets set for him.
"On the field, that entailed reaching cup finals, achieving a third-place finish and reaching European competition. Those moments will live long in the memory of supporters and will go down in our history.
"Off it, his success in player development and sales has ensured this club is in a strong financial position. His ability to rear new talent was commendable and delivered great benefit to us.
"He is a man who has conducted himself exceptionally well and has been a figurehead for our club for the last three-and-a-half years.
"It has been a privilege to work with him over these years. We all wish him well for the future."