Huddersfield have announced the departure of manager David Wagner by mutual consent.
The Terriers sit bottom of the Premier League after Saturday's goalless draw at Cardiff halted a club record nine straight defeats.
"David Wagner has departed his role as head coach of Huddersfield Town by mutual consent," read a club statement.
"The 47-year-old leaves Town after detailed discussions with the board of directors, with both parties agreeing this is the correct move for the future of the club."
Wagner, who signed a new three-year deal in May last year, led the club into the top tier from the Sky Bet Championship and kept them up last season.
Huddersfield chairman Dean Hoyle said: "I'd like to begin by thanking David for all he has achieved at Huddersfield Town over the last three-and-a-half years.
"Under his stewardship, we've achieved things on the football pitch that surpass anything in modern memory, and that have gone well beyond my wildest expectations as chairman and as a fan.
"Under David's management, we took this club to the highest position it has held in almost 50 years and created memories that will last forever.
"His achievements will rightly put him up there in Huddersfield Town history alongside great names like Herbert Chapman and Mick Buxton - legendary managers who changed the face of this club.
"As I had said previously, I had no intention of sacking David this season. Subsequently David - being the great man he is - came to us and made it clear that he needs a break from the rigours of football management."
Hoyle confirmed under-23s coach Mark Hudson will take charge for Sunday's league game against Manchester City.
Wagner was unknown in this country when he replaced Chris Powell in November 2015 after leaving his role as head coach of Borussia Dortmund reserves.
He steered the Terriers away from relegation trouble and then in his first full season led them to an unlikely promotion to the Premier League in 2017.
The Terriers had started the campaign as relegation candidates, but finished it by returning to the top flight for the first time in 45 years.
Town defied all the odds again to avoid an instant return to the Sky Bet Championship last season when clinching a point at Chelsea in their penultimate game.
They invested £40million on new players during the summer, but this season had to wait until November before winning their first game at the 11th attempt.
Victory at Wolves at the end of that month lifted hopes they could launch another great escape, but eight successive league defeats followed before another loss at Bristol City in the FA Cup.
Town are currently eight points adrift of safety at the foot of the table.
Hoyle had said that he would not sack Wagner, even if the club were relegated, and reminded fans of that promise in October.
The Terriers' owner and chairman added: "After a long discussion we all felt that David staying at the club until the end of the season was best, but we've kept discussions open and we all now feel that the time is right to part ways.
"I know the term 'mutual consent' is often a byword for the manager being sacked in professional football, but this is a truly joint decision.
"David has a real, genuine love for this club and, like me, his foremost concern in our talks has been to establish what is best for Huddersfield Town.
"I cannot thank David enough for what he has achieved. Along with his family, he will always be a friend to me and Huddersfield Town."