Leeds United parted ways with Argentine manager Marcelo Bielsa on Sunday (Feb 27) after their 4-0 home loss to Tottenham Hotspur left the club hovering above the Premier League relegation zone.
Bielsa, appointed in 2018, took Leeds back into the top flight for the first time in 16 years and they finished ninth last season.
Defeat by Spurs was their fourth straight loss, however, and they conceded 17 goals in those matches, leaving them in 16th place, two points above the relegation zone.
"This has been the toughest decision I have had to make during my tenure at Leeds United, taking into account all the success Marcelo has had at the club," Leeds chairman Andrea Radrizzani said.
Bielsa became a hugely popular figure at Leeds after ending their years outside of the Premier League and restoring them to the top flight with an entertaining brand of high-energy attacking football.
"He changed the culture of the club and brought a winning mentality to us all. The moments created, particularly in the 2019/20 season and winning promotion to the Premier League, will of course live long in all our memories, myself and the fans included," Radrizzani said.
"However, I have to act in the best interest of the club and I believe a change is required now in order to secure our Premier League status. Recent results and performances have not met our expectations."
Leeds said they had plans for a "permanent tribute" to Bielsa at their Elland Road stadium.
They are planning to make an announcement about Bielsa's replacement on Monday.