The Spanish winger was absent from the squad that secured a 2-1 victory over Bournemouth last Saturday, with some Everton supporters questioning where he was.
Deulofeu posted an image to his twitter account late on Wednesday, saying “Recovery with ice before Champion’s League”.
And manager Roberto Martinez confirmed the 21-year-old’s knock at his pre-match press conference ahead of the match against Leicester City this weekend.
“Gerard Deulofeu – it will be difficult to see him in any of the three games that are left,” Martinez said.
— Gerard Deulofeu (@gerardeulofeu) May 4, 2016
“We had no new knocks or problems in the game against Bournemouth. The only three players we are keeping a close eye on are Seamus Coleman, Gareth Barry and Phil Jagielka,” the 42-year-old added.
“Gareth and Seamus have got an outside chance of being involved at the weekend but I feel quite confident they will be involved one way or another before the season ends.
“We are confident Phil Jagielka will be available for the last game of the season.”