Northern Ireland have been handed a triple injury blow ahead of their 2014 World Cup qualification campaign.
Paddy McCourt has been ruled out of the opening double-header against Russia and Luxembourg while Martin Paterson (hamstring) and Shane Ferguson (groin) will miss the initial trip to the Russian capital on Friday.
Paterson and Ferguson could return for the Luxembourg game at Windsor Park next Tuesday.
A statement from the Irish Football Association read: "The players will remain with their clubs and will be assessed later in the week ahead of Northern Ireland's home game against Luxembourg on Tuesday (September 11)."
Michael O'Neill has not yet named any replacements as he takes charge of his first competitive game on Friday.