Rafa Benitez blamed circumstances and injuries for Everton's poor results, and lamented a lack of patience after he was sacked by the Merseyside club.
Everton fired the Spaniard in the wake of Saturday’s 2-1 defeat to relegation-haunted Norwich City that left the Toffees only two places above the Premier League drop zone, having won just one of their last 13 league games.
His appointment in June raised eyebrows given his ties to neighbours Liverpool, who he guided to the Champions League title in 2005.
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And Benitez acknowledged he had failed to win over the hearts of fans, but also blamed the team's many injuries as the main reason for such a disappointing campaign.
"From the very first day, my staff and myself worked as we always do, with commitment and full dedication, we didn't only have to get results, but we also had to win over people's hearts," Benitez said in a statement.
"However, the financial situation and then the injuries that followed made things even harder. I am convinced that we would have been better once the injured players were back and with the arrival of the new signings.
"The road to success isn't easy and sadly, nowadays in football there is a search for immediate results and there is always less and less patience; unfortunately circumstances have determined the results and it won't be possible to continue this project."
Benitez, who was facing increasing opposition from supporters as the season went on, also thanked "those fans who have supported us during this time."
Everton started the season in terrific form and looked outside contenders for a Champions League berth, but an astonishing slump in form now leaves them facing a relegation battle.
The club said they would announce a permanent successor soon.
A host of names are already being linked with the job, including Frank Lampard, Derby boss Wayne Rooney and ex-coach Roberto Martinez.
Everton are next in action against Aston Villa in the league on Saturday.
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