Roy Hodgson has stepped down as Crystal Palace boss so the club can “bring forward their plans to appoint a new manager”.
Hodgson, 76, was “taken ill” during training on Thursday amid reports he was to be sacked.
The Eagles have lost 10 of their past 16 Premier League games and are 16th in the table, five points above the relegation zone.
“This club is very special and means so much to me,” said Hodgson.
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Former Eintracht Frankfurt boss Oliver Glasner, 49, is the strong favourite to replace Hodgson on a permanent basis.
“I have fully enjoyed my time here across six seasons, as it has given me the chance to work with top-class players and staff doing what I love every day,” added Hodgson.
“However, I understand, given recent circumstances, it may be prudent at this time for the club to plan ahead, and therefore I have taken the decision to step aside so that the club can bring forward their plans for a new manager, as intended for this summer.
“I am confident that the season will finish well and I wish the team every success in the weeks, months and seasons to come.”
The club said Hodgson was now out of hospital and “doing well”.
“Roy has a special place in Crystal Palace history and this will never be forgotten,” said chairman Steve Parish.
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