Long, who has scored nine times in his last 11 appearances for the Royals, needed an injection in his hip to play against leaders QPR last Friday and for Republic of Ireland against Wales in midweek so will be checked on.
Wales striker Simon Church is likely to be partnered by Noel Hunt if Long is ruled out as manager Brian McDermott has stated that exciting new signing Mathieu Manset is not yet ready to start a game.
Midfielder Brian Howard is back in contention after recovering from his toe injury and defender Alex Pearce is also back in the squad after a thigh complaint.
Mikele Leigertwood serves the second game of a three-match ban after he was charged for violent conduct by the FA following the recent draw at Cardiff.
Source: PA
Source: PA