Gianfranco Zola has resigned as Birmingham City manager following Monday's home defeat by fellow Championship strugglers Burton Albion.
The 50-year-old Italian was in charge for just four months, during which time the team won only twice in 24 games.
Their 2-0 loss to Burton left them 20th in the Championship table, just three points above the relegation places with three games remaining.
"I sacked myself. I decided to give in my resignation," said Zola.
"I am sorry because I came to Birmingham with huge expectations. Unfortunately, the results have not been good and I take full responsibility.
"It is not that I like quitting, but Birmingham deserves better. If I feel I cannot help the players, why stay? If I cannot help the team, it is better I leave and let someone else do that.
"I feel very bad and very sorry. We worked with a lot of meaning, but unfortunately it didn't produce the results. It is all very disappointing."
The swapping of Rowett for Zola
When predecessor Gary Rowett was sacked in December, Blues were seventh and only out of the play-off places only on goal difference.
Club director Panos Pavlakis explained their decision to dispense with Rowett, now in charge at Derby County, by saying that Zola's "pedigree" matched their ambition to "move in a new direction".
But the change of manager baffled many supporters - and results on the pitch have done nothing to win them over.
Chinese-owned Birmingham issued a statement on 10 April giving Zola their full backing following a 2-1 defeat by Rowett's Rams.
But the loss to Burton, another of Rowett's old clubs, leaves Blues without a win in nine games since beating local rivals Wolves at Molineux in February - and Blues have picked up just 16 points out of a possible 66 in Zola's time in charge.
Blues' next game is at local rivals Aston Villa on Sunday (12:00 BST).
If 22nd-placed Blackburn, who are at Wolves, and 21st-placed Nottingham Forest, who are at home to Reading, were both to win their respective games on Saturday, Blues would start the game at Villa Park in the bottom three.
It is the second time former Chelsea and Italy striker Zola has resigned as manager of an English club, having quit Watford in 2013 after five successive home defeats. He also spent two years in charge of West Ham United.
BBC WM's Richard Wilford
"Gianfranco Zola's ill-fated tenure at St Andrew's arguably could have been cut short sooner than it was. By his own admission, he felt he could not help the players any more.
"In a dignified media conference after his resignation had been announced, Zola noted that he had felt pressure from the very outset, given the success the club had under his predecessor Gary Rowett.
"Results are king in football, and two wins in 22 league games was unacceptable. Zola may have lacked fortune while he was in charge at Blues, but not so much as to justify such a paltry return.
"The Easter performances against Rotherham and Burton were limp, listless and damning. Birmingham's flirtation with relegation is very real indeed."