Jamie Osbourne has been ruled out of Ireland's two remaining November internationals against Australia and South Africa.
The Leinster full-back was taken off with a suspected dislocated shoulder during Saturday's 41-10 victory over Japan at Aviva Stadium, and the IRFU has confirmed that the injury is serious enough to take him out of the clashes with the southern hemisphere sides.
Mack Hansen would be one candidate to slot into the back three. The Connacht wing has linked up with the squad, but the IRFU stating he "continues to make positive strides in his rehabilitation" suggests this Saturday may be too soon for a starting berth.
Stuart McCloskey is nursing an adductor problem, but is expected to take a full part in training this week.
Garry Ringrose and Josh van der Flier, who both have hamstring niggles, are training but a decision on their inclusion in the match day squad for Saturday's clash with Australia won't be made until later in the week.
The Ireland team to face Australia will be named on Thursday afternoon.
Watch Ireland v Australia in the Quilter Nations Series on Saturday from 7pm on RTÉ2 and the RTÉ Player. Follow a live blog on the RTÉ News App and on rte.ie/sport. Listen to live commentary on RTÉ Radio 1
