Ireland will be without influential hooker Dan Sheehan and scrumhalf Craig Casey for Saturday's second Test against the Springboks in Durban.
Both were injured in last weekend's 27-20 defeat to the Springboks at Loftus Versfeld and their participation in this week's Test was in immediate doubt.
The loss of Sheehan, who suffered a knee injury, is a serious blow to Ireland. He provides grit and grunt that is hard to replicate.
Many in the northern hemisphere regard him as the best hooker on the planet.
Sheehan was injured at Loftus in a first half collision with Bok lock Eben Etzebeth.
