Eriksen left Old Trafford on crutches on Saturday after being caught by Reading striker Andy Carroll in the fourth-round tie.
The loss of the 30-year-old Danish playmaker is a blow for United who lie fourth in the Premier League and in the Champions League qualification places after a good run of form that only ended with the 3-2 defeat by leaders Arsenal on January 22nd.
United said in a statement: “Christian Eriksen is expected to be out of action for an extended period because of an ankle injury sustained in our FA Cup victory over Reading on Saturday.
“While investigations are continuing, initial assessments indicate that Eriksen is likely to be out until late April or early May.”
United said, “there is hope that Christian can return in time to play a role in the final stages of the campaign”.
