Leicester City have sacked manager Nigel Pearson, saying the working relationship between him and the club's board was "no longer viable".
Pearson, 51, guided the Foxes to 14th in the Premier League in 2014-15.
But he was involved in several high-profile incidents, including calling a journalist an "ostrich" and clashing with Crystal Palace's James McArthur.
"It has become clear that fundamental differences in perspective exist between us," said a club statement.
Pearson first became manager of Leicester in June 2008 but left two years later to take over at Hull before returning to the Foxes in November 2011.
They clinched the Championship title in 2013-14 and won seven and drew one of their last 10 games last season to secure Premier League survival.
The Leicester statement - which thanked Pearson for his "considerable contribution" - added: "The board of directors recognises the success Nigel has helped to bring to Leicester City during his two spells in charge, particularly during the last three and a half years."
In June, Pearson's son James was one of three players sacked by the club for their involvement in a racist sex tape, while on a tour in Thailand - home of the club's billionaire owners, Vichai Srivaddhanaprabha and son Aiyawatt.
The decision comes just days before the players report back for pre-season training on Monday. The squad will include three new summer signings, Japan striker Shinji Okazaki, Austrian defender Christian Fuchs and Robert Huth, from Stoke.
Craig Shakespeare and Steve Walsh will take charge of first-team duties while the club begins its search for a new manager.
Pearson won the Premier League Manager of the Month award for April, but his season was not without controversy.
'I think you're an ostrich'
Pearson called a journalist an "ostrich", "stupid" and "daft" during a bizarre post-match news conference following Chelsea's 3-1 win at the King Power Stadium in April.
After Pearson referred to "the amount of criticism and negativity" his side had faced, Ian Baker of Wardles Press Agency asked the Foxes boss to elaborate.
The Leicester manager replied: "You must have been either head in the clouds or away on holiday because your question is absolutely unbelievable.
"If you don't know the answer to that question, then I think you are an ostrich. Your head must be in the sand. Is your head in the sand? Are you flexible enough to get your head in the sand? My suspicion would be no."
Confrontation on the pitch
Pearson also made headlines with a strange touchline clash with Crystal Palace midfielder McArthur in February.
After the pair collided, it looked as though both parties would laugh off the incident.
But Pearson grabbed McArthur by the throat before preventing him from returning to the field by pulling his shirt.
Asked why he had held McArthur back, Pearson said: "Because he said something to me. I'm more than capable of looking after myself. There's no problem with the player."
The Football Association wrote to Pearson to remind him of his responsibilities but did not charge him.
Sacked, or not sacked?
After the incident with McArthur, media reports suggested Pearson had lost his job, but the club issued a statement saying said the rumours were "inaccurate and without foundation".
With the club then bottom of the Premier League, Pearson said he "had conversations" about his job but would not reveal the details.
"If I have got things to say I will say it in the appropriate manner to the appropriate people," he added. "I don't think I've been in a position where I speak too openly about what goes on in internal workings.
"I've always had a good working relationship with the owners and I'm sure I will moving forward."
Banned and fined after supporter altercation
In December 2014, Pearson was given a one-game touchline ban and fined £10,000 for insulting a fan during Leicester's 3-1 Premier League loss to Liverpool.
Pearson declined to reveal what was said during the altercation with the supporter, but said he felt it necessary to protect his players and himself from abuse.
He was called arrogant by the chairman of a Leicester supporters' group after he refused to apologise.
'Major shock' - Phil McNulty, BBC Sport chief football writer
"Had Leicester sacked Nigel Pearson at various stages last season it would not have raised an eyebrow - to dismiss him now after brilliantly engineering an escape from what seemed certain relegation is a major shock.
"Pearson's season was chequered to put it mildly. And yet he kept his nerve to produce a stunning end to the campaign that kept Leicester City in the Premier League against all the odds. Pearson ended last season as a hero to the Foxes fans.
"It looked to have secured his future and the "fundamental differences in perspective" after that have led to his demise remain a mystery. He did the hard yards in keeping Leicester up - now someone else will take the Foxes forward."
Match of the Day presenter and ex-Leicester striker Gary Lineker: "Leicester City have sacked Nigel Pearson. Really? Could you kindly reinstate him like the last time you fired him?"
Former Liverpool defender Jamie Carragher: "And people ask why the modern player chooses punditry."
BBC presenter Dan Walker: "Football is a bit daft sometimes."