O'Driscoll sustained a tight calf during training earlier in the week and was rated a slight doubt for the Croke Park showdown against the Scots.

The 29-year-old completed a practice session on Thursday and showed no reaction to the problem, but Ireland must wait for an update on his availability.

Girvan Dempsey has joined O'Driscoll in the treatment room, after taking a knock to his left hip in training.

Leicester's Geordan Murphy, initially dropped from the 22 following a poor display in the 26-21 defeat by France, is on stand-by.

Dempsey will also undergo a fitness test on Friday - with Murphy, who had been selected for Saturday's clash against Sale, ready to slot in at full-back if he fails to get the green light.

Tony Buckley's place on the bench has been confirmed after the giant Munster prop passed a fitness test on his thumb injury on Thursday.