Prop Cian Healy has been ruled out of Ireland's opening World Cup match against the United States in New Plymouth on Sunday.
The 23-year-old Leinster forward has recovered from the eye injury he sustained in the defeat by England in Dublin last month but has not yet started contact training.
However, Ireland are confident that he will be available in time for the crunch Pool C clash with Australia on September 17th.
"Cian won't be playing at the weekend," said Ireland team manager Paul McNaughton.
"He won't resume contact work until the weekend, which was the original prognosis, so he won't be available for the USA game but will be available for the Australia game.
"He's been able to do a couple of scrums but not as much as normal."
In better news for Ireland, centre Gordon D'Arcy and back-rower Sean O'Brien have been passed fit for the United States game.
D'Arcy has been struggling with a calf injury while O'Brien has had a knee problem.
"We're dealing from a full deck outside of Cian," added McNaughton. "Everybody else is fit and strong and available for selection."
McNaughton confirmed that there will be a 30-second silence before the match to mark the 10th anniversary of the September 11th attacks. Both teams will wear black armbands.
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