Paul Clement has been sacked as manager of Swansea, with his assistant managers Nigel Gibbs and Karl Halabi also leaving the club.
Clement, 45, had been under increasing pressure and the Swans confirmed his departure after Monday night's 3-1 defeat at Everton left them four points adrift of safety.
Swansea are in serious danger of relegation this season and have won once in 11 games, which prompted the move.
We can confirm that the club has tonight parted company with head coach Paul Clement.
- Swansea City AFC (@SwansOfficial) December 20, 2017
Swansea chairman Huw Jenkins confirmed: "To change the manager, especially at only the halfway point of the season, is the last thing we wanted to do as a club.
"We had three different managers last season and as a result we all wanted to give Paul as much time as possible to turn things around. But we felt we couldn't leave it any longer and needed to make a change to give us the best chance of an uplift and a turnaround in fortunes with the club bottom of the Premier League.
"Paul has been at the club for 12 months and what he achieved in the second half of last season to keep us in the top flight was a tremendous feat. For that, and his effort and commitment this season, it goes without saying that the club thanks him for his work, together with Nigel (Gibbs) and Karl (Halabi).
"I have had an excellent working relationship with Paul and we are all, including the owners, surprised and disappointed it hasn't worked out this season. We wish Paul every success in his career going forward.''
Three wins and three draws from the opening 18 games leave the Swans bottom of the Premier League on 12 points and the club insisted it would "give supporters a further update regarding their replacements within the next 24 hours."