Stoke have sacked manager Gary Rowett after just eight months in charge.
The Potters were among the favourites for promotion from the Sky Bet Championship this season but have underwhelmed and currently lie 14th in the table, eight points off the play-off spots.
Rowett's coaching staff have also left the club, leaving Rory Delap, Kevin Russell and Andy Quy to take temporary charge of the first team.
A Stoke statement read: "The club would like to thank Gary and his staff for their efforts over the past eight months.
"A new managerial appointment will be made as swiftly as possible."
Rowett signed a three-year deal with Stoke in the summer after the relegated Premier League side paid Derby £1.8m in compensation for his signature.
However, they have not won in their last four matches and were held to a 1-1 home draw by League One Shrewsbury in the FA Cup on Saturday.
Rowett began his managerial career at Burton in 2012 and guided them to the League One play-offs on two occasions before joining Birmingham.
He was controversially sacked in December 2016 despite being on course to take the Blues into the play-offs, before moving to Derby.
Stoke's attention will now turn to finding a permanent replacement for Rowett, with reports suggesting the Potters have been considering David Moyes and Sam Allardyce.
However, sources have told Sky Sports News that former England manager Allardyce is not a contender for the job at the bet365 Stadium.