Nottingham Forest forward Jamie Ward, who is currently on loan at Burton Albion, suffered a broken wrist during his side’s Championship clash with Barnsley at the weekend and is expected to spend several weeks on the sidelines.
Dallas, meanwhile, has not featured since picking up a calf injury against San Marino during the last international break and will continue his recovery at Leeds United .
Manager Michael O’Neill has opted not to call up any replacements for the injured duo, deciding instead to stick with a 23-man squad.
Northern Ireland currently sit third in Group C, three points adrift of Azerbaijan heading into Friday’s match in Belfast.
O’Neill’s side will then host Croatia in a home friendly in their final match of 2016.