Brighton have sacked manager Chris Hughton after they finished 17th in the Premier League.
The Seagulls won just three of their last 23 league games and none of their final nine.
Chairman Tony Bloom said that run “put our status at significant risk”.
Hughton, who joined Albion in December 2014, led the club to the Premier League for the first time in 2017, and they finished 15th in their first season back in the top flight.
Swansea boss Graham Potter, 43, who joined the club from Swedish side Ostersunds in 2018, is the favourite with the bookmakers to replace Hughton.
Hughton, 60, who was contracted until 2021, also took the club to the FA Cup semi-final this season, where they lost 1-0 to Manchester City.
Bloom said: “Our run of three wins from 23 Premier League matches put our status at significant risk. It is with that in mind, and the performances during that period, that I now feel it’s the right time for a change.
“Undoubtedly, this has been one of the most difficult decisions I have had to make as chairman of Brighton, but ultimately one I have made due to how we struggled in the second half of the season.”
Hughton won 40.93% of his 215 games in charge and was named the Premier League’s manager of the month in March 2018.
He is the seventh Premier League manager to be sacked this season.
Bloom praised Hughton for an “excellent job” in stabilising the club, achieving promotion and retaining their Premier League status.
“Chris will always be very fondly remembered by Albion staff and fans as one of our club’s finest and most respected managers,” he added.
Fan website wearebrighton.com said most would “feel pity for Hughton” and that the sacking represented a “huge gamble” for Bloom in the “cut-throat world of modern day football”.
“There are countless tales of woe of clubs getting rid of managers in favour of trying something new, only for it to end in tears,” it added, citing departures such as that of Alan Curbishley from now-League One Charlton Athletic.
But it said Hughton’s record in the second half of the season meant there could only be one outcome: “There is no getting away from the fact that since Christmas, they have been nowhere near good enough – and not many clubs would stick with a manager who was delivering so little over the course of five months.”