Swansea chairman Huw Jenkins has admitted the decision to part company with manager Michael Laudrup was "taken reluctantly" but believes it is in the best interests of the club.
The Dane has left the Swans with immediate effect on Tuesday night with veteran defender Garry Monk and first-team coach Alan Curtis to take charge of the team ahead of Saturday's clash with rivals Cardiff.
The news ends considerable speculation over Laudrup's position, which had been growing since last weekend's loss to West Ham.
The Capital One Cup-winning boss' relationship with the club had reportedly been strained since a major disagreement over transfer policy last summer.
The 49-year-old had also been under increasing pressure after a run of just one win in 10 Barclays Premier League matches left the Swans just two points above the relegation zone.
Jenkins said: "It is a decision we have taken reluctantly, but it's a decision made in the best interests of Swansea City Football Club and our supporters.
"It is the first time in nearly 10 years that the club has parted with a manager in this way, but we had to remove the constant uncertainty surrounding the club and Michael's long-term future with us.
"I had a meeting with Michael today in a final attempt to support him and establish a way to improve the work of the backroom team to secure the results we need over the final 14 Premier League games.
"However, after thinking long and hard about the best way forward, I felt it was unlikely we would achieve a stable environment at the club to allow us to get back to basics and produce the performance levels that have served Swansea City so well over the last few years.
"Now we need to put that uncertainty behind us and move forward as a united football club on all fronts, while placing on record our gratitude to Michael for the work he has done over the last 18 months and wish him well for the future."
Laudrup, the former Real Madrid, Barcelona and Denmark midfielder, was appointed in the summer of 2012 having previously managed at Brondby, Getafe, Spartak Moscow and Real Mallorca.
Last season's Capital One Cup success - Swansea's first major trophy - enhanced Laudrup's reputation considerably and he was rewarded with a lucrative new contract until 2015.
However, problems surfaced last summer when it is thought Laudrup and Jenkins fell out over transfer targets. The difficulties led to the club's refusal to deal with Laudrup's representative Bayram Tutumlu in transfer deals.
Press Association Sport understands tensions have also remained throughout the current season and there has also been disquiet about the intensity of training sessions.
Prior to Laudrup's exit, it had been understood that Monk, who has not played since September after undergoing knee surgery, was being lined up for a coaching role.
The long-serving Monk, 35 next month, joined the Swans when they were in League Two in 2004 and he and Curtis have now been put in charge for the "foreseeable future".
The Supporters' Trust, which has more than a 20 per cent shareholding of the football club, backed the decision to part company with Laudrup and called on fans to get behind Monk and the players "in the tough battles ahead".
In a statement, the Trust said: "During its tenure at the club, the current board, including a representative of the Supporters' Trust, has made key decisions which have taken the club forward, and ultimately we believe that this decision has been taken with the best interest of the club in mind."
And chairman Phil Sumbler added: "There has inevitably been a mixed reaction among fans to the announcement, with the club facing a critical period of key matches in three major competitions.
"However, we know from our supporter director Huw Cooze that the board has not taken this decision lightly, particularly in such an important week for the club, and it's vital that we now all pull together to give the team our full support.
"We all want to see an upturn in results, and what better place to start than at the Liberty Stadium against Cardiff City?"
The Trust has also placed on record its thanks to Laudrup for his achievements during his time at the club.
Swansea later confirmed on the club website that three of Laudrup's backroom staff have also departed the Liberty Stadium.
"The club can confirm that assistant manager Morten Wieghorst, fitness coach Oscar Garcia and overseas scout Erik Larsen have all been relieved of their duties," Swansea said.
"The club would like to thank them for their services."
Laudrup handed former Denmark, Celtic and Dundee midfielder Wieghorst the assistant manager's role a year ago.
Wieghorst, 42, was Denmark Under-21s manager before moving to Wales.