Kenny Jackett has resigned as Rotherham manager after just five games - and 39 days - in charge.
Jackett was appointed as Alan Stubbs' successor on October 21, but after taking just one point from his first five games he has decided to walk away.
That leaves the Millers, who are 11 points from safety in the Championship and set for a return to League One, looking for a third manager of the season and a sixth in 14 months.
A club statement read: "Following the game against Leeds United at the weekend, Kenny Jackett tendered his resignation and accordingly, his employment with the club has terminated with immediate effect.
"Kenny's resignation came as a shock to the club and is disappointing. The club will now focus on making appropriate arrangements for the first team."
Jackett signed a three-year contract at New York Stadium, but has barely seen out more than a month, making him officially the shortest-serving permanent manager in the club's history, taking the record from the man he replaced.
His reign started off in positive fashion with a improved performance against Reading and a draw at Ipswich, which was seconds away from being a win, but the following three games have been a step back.
Defeats against Preston, Leeds and Derby extended the club's winless run to 14 games and left them effectively 12 points from safety and almost certainly heading into League One.
Chairman Tony Stewart must now begin yet another managerial search, his fifth since the departure of Steve Evans in September 2015.
Fitness coach Paul Warne will take over on an interim period.
The news could not have come at a worse time for the Millers as they go into a period of games that could potentially see them claw some of that deficit back, starting at Burton on Saturday.