Portsmouth have lost seven of their last eight league games
Portsmouth have dismissed manager Tony Adams and first-team coach John Metgod following a run of poor results.
A club statement said it was a "difficult decision", taken after Pompey won just two out of 16 Premier League games since Adams took charge.
Adams told BBC Radio Solent he was "surprised" to be sacked.
"Results have not been good, it must be said, but we're not getting done sixes and fours and performances on the whole have been good."
Director of youth operations Paul Hart will take over as caretaker manager for the time being, but that role could be very short-term, with ex-Chelsea boss Avram Grant favourite to replace Adams, who had only been in the job since late October.
BBC Radio 5 Live's senior football reporter Ian Dennis said: "Portsmouth hope to have a new manager installed ahead of Saturday's vital home game against Manchester City.
"In the running are Avram Grant, who was director of football at Fratton Park three years ago, ex-West Ham boss Alan Curbishley and I also hear Graeme Souness has been sounded out.
"Grant is considered to be the favourite."
MANAGERIAL DEPARTURES 2008-09
Sep 3: Alan Curbishley - West Ham
Sep 4: Kevin Keegan - Newcastle
Oct 25: Juande Ramos - Tottenham
Oct 26: Harry Redknapp - Portsmouth
Dec 4: Roy Keane - Sunderland
Dec 16: Paul Ince - Blackburn
Feb 9: Tony Adams - Portsmouth
On Saturday, Pompey were beaten at home 3-2 by Liverpool despite leading 2-1 with only five minutes to go.
Prior to the defeat by Liverpool - their seventh loss in eight games - Adams had insisted he had the backing of the club chiefs.
Portsmouth are currently 16th in the table, one point above the relegation zone, with 14 games to play.
The club's statement added: "The owner and the board feel they have been as supportive as they can during a period when results have been poor.
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