Belgium international Mirallas suffered a hamstring strain in last week’s 2-1 win over Sunderland, while Irish international Gibson has been out since September with a thigh problem.
In his pre-match press conference, Moyes told reporters: "Kevin is out injured, but we don't think it's too bad at the moment. Darron is still injured."
Striker Victor Anichebe and right-back Tony Hibbert will undergo fitness tests on Friday but are doubtful, having missed last week’s victory over the Black Cats, with Seamus Coleman and Steven Naismith possible replacements.
|14/1||Reading are 14/1 with bet365 to break their duck and beat Everton 2-1|