Everton sacked manager Sam Allardyce on Wednesday after a six-month reign that saw the former England national team boss steer the Merseyside club to eighth place in the Premier League.
Allardyce, who replaced sacked Dutch manager Ronald Koeman in November with the club 13th and five points above the relegation zone, still had a year to run on his contract.
"On behalf of the Chairman, Board of Directors and Mr (Farhad) Moshiri, I'd like to thank Sam for the job he has done at Everton over the last seven months," Everton's newly-announced CEO Denise Barrett-Baxendale said on the club's website.
"Sam was brought in at a challenging time last season to provide us with some stability and we are grateful to him for doing that. However, we have made the decision that, as part of our longer-term plan, we will be appointing a new manager this summer and will be commencing this process immediately."
Despite a doing a solid job, the 63-year-old Allardyce had fallen out with a large majority of Everton's fans who were not impressed with his management style.
Allardyce, who was briefly England manager in 2016 before returning to club management at Crystal Palace last season, had already reacted angrily to the structural changes at the club prior to his meeting with majority owner Iranian-born British tycoon Farhad Moshiri.
"I'm shocked, disappointed and disgusted that the football club didn't have the decency to tell me, my Director of Football and my staff about the changes," he told the Liverpool Post on Tuesday.
"They must have been in the pipeline for a considerable time but no-one thought to tell me and my staff."
Former Watford and Hull City manager Marco Silva is one of the favourites to take over at Goodison Park.
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