Carlo Ancelotti has revealed midfielder Allan will miss the "period of matches” over Christmas and added the Club are still assessing the exact timeframe of the hamstring injury the Brazilian sustained in Wednesday’s 2-0 win at Leicester City.
Ancelotti says it is not expected Allan will require an operation.
The Everton boss added James Rodriguez will not be available for Saturday’s Premier League game against Arsenal (5.30pm GMT) – but skipper Seamus Coleman is in line to make his First-Team comeback in the Goodison Park clash.
James continues to be sidelined with a calf injury which has kept him out of the Blues’ victories over Chelsea and Leicester.
Ancelotti believes the Colombian could be ready to face Manchester United in Wednesday’s Carabao Cup quarter-final at Goodison.
Coleman, however, will be available on Saturday to make his first Everton appearance since the Blues’ Premier League game against United on 7 November.
Fabian Delph will miss the Arsenal match with a hamstring injury and Lucas Digne remains out with an ankle ligament problem.
Jean-Philippe Gbamin is continuing his rehabilitation from an Achilles injury.
“Allan had a problem on his hamstring and we don’t know [exactly] how many games he will be out for," said Ancelotti, who was speaking at his pre-match press conference.
“But for the games in this period, he is not going to play.
“Seamus Coleman is available.
"Seamus has a strong desire to play. He is a fantastic captain for us and it is really important he is back.
“James is not ready yet. I think it is too soon to put him at risk.
“He is working and I hope he can be ready for the game against United.
“Fabian Delph is doing individual treatment. It is too soon to talk about how long it will be before he comes back.”