Ireland coach Joe Schmidt has been dealt a second blow this evening with the news that Ulster second-row Iain Henderson is set to be sidelined "for several weeks".
The northern province released a statement saying Henderson had "suffered a finger injury" in Ulster's win against Leicester in the Champions Cup on Saturday, following on from the news that Tadhg Beirne picked up a knee injury playing for Munster over the weekend.
Ulster say it is a fresh injury and is unrelated to the second row's thumb injury, which had kept Henderson out for the last number of weeks.
The game was Henderson's 100th cap for the province.
The injury is likely to rule Henderson out of Ireland's opening Six Nations fixture against England on February 2.
The IRFU announced earlier today that Beirne is set to miss the opening two rounds of the Six Nations after a scan revealed his knee injury.
Connacht's Quinn Roux has been called up in his place.
He will join the three remaining second rows in the Ireland camp, who are Devin Toner, James Ryan and Ultan Dillane.
Ulster also announced that Sean Reidy picked up a hand injury which will require surgery in the Leicester game while Billy Burns sustained a concussion and must now follow return to play protocols.
Marcell Coetzee also sustained a hamstring injury which the province say will be scanned today.
Munster are also set to be without flanker Tommy O'Donnell who suffered another serious injury in the province's game against Exeter.