Livingston are looking for a new head coach to fit into their management structure after Gary Holt resigned.
Holt, 47, had questioned his own future after a 1-0 home defeat by St Mirren on Saturday left Livi sitting in 10th place, without a win in five Scottish Premiership games.
The former Falkirk boss, who led Livi to ninth and fifth-placed finishes, decided to walk away following talks with the club.
In a statement on the club's official website, Holt said: "It is with great regret that I have made the difficult decision to resign as manager of Livingston FC.
"This is not a decision that I have taken lightly but feel it is the right time for me to step away.
"I am proud to say the work we have done over the past two years has resulted in great success both on and off the pitch."
David Martindale, who shared the dugout with Holt and plays a major role in recruitment through his position as head of football operations, will take temporary charge for Saturday's Betfred Cup clash with Ayr.
Martindale stressed the decision to walk away was Holt's alone and added: "I never tried to persuade him to stay. He's a grown man, he knows his mind better than me.
"Our physio was leaving six weeks ago and I never spoke to the physio about trying to stay.
"Was I gutted he's leaving? Of course I was. We have a great staff, a great morale. We are going through a bit of a sticky spell but it affects everyone differently.
"I'm more than culpable. I'm as culpable as Gary about results. So I feel a bit bad in that respect but I will take that on the chin.
"I think it's testament to Gary. He could have sat here to the end of the season, he could have sat here to January a wee bit unhappy, and took his wages.
"In the pandemic when there's not a lot of work going about, I think it speaks volumes for Gary and the man he is. I think it's a very, very brave decision but a very, very honest decision. You don't see a lot of that in football."
After Saturday's defeat, Holt admitted the players might need a fresh voice.
"Gary, from when he first came in, always said managers had a two or three-year shelf life," Martindale said.
"When I was involved in the recruitment of Gary and had a massive say in Gary coming in, that was always one of the things we said: come in, do well, and get yourself away.
"Because with all due respect to Livingston, you'll be comfortable but there are probably a lot better-paid jobs out there.
"If it wasn't for Covid, I quite believe Gary would have probably got a better opportunity in the summer."
Martindale confirmed Livingston would seek "someone that's going to fit into the current structure" as a replacement.
"They are a cog in the wheel," he said. "When that cog stops working, the other cogs need to keep working away.
"I find that some clubs, when managers leave, there's a full change of department. Physios go, kit men go, players go. That doesn't happen here, we don't have the finances for that to happen.
"The role has always been a head coach. Look where we are and where we've come from, four or five years ago we were in League One. So we are doing something right with the staff that's at the club. I would imagine a lot of managers would see it as an attractive opportunity."
When asked whether he wanted the job himself, Martindale said: "I have been offered the job before but I didn't think it was right for my career development.
"If we can win on Saturday we are one game away from Hampden. All my efforts are concentrating on Ayr United on Saturday."