McFadden drafted in for Earls

Earls' partner Edel McGee gave birth to their first child, Ella-Maye, last week only for the baby to return to hospital on Wednesday because of an unspecified illness. It was decided in conjunction with coach Declan Kidney that the 24-year-old Munster back should miss Sunday's showdown in Dublin.

McFadden has been promoted to the starting line-up with the uncapped David Kearney, brother of full-back Rob, drafted on to the bench. Team manager Michael Kearney: "Keith has been ruled out due to personal reasons. Unfortunately his baby has been taken ill and is in hospital as we speak. The nature of the illness is unclear."

He added: "However, I did speak to Keith this morning and he was hopeful and optimistic that the baby would get home some time over the weekend. The decision was taken following a conversation between Declan and Keith yesterday (Thursday).

"It was thought that it was in the best interests of Keith, his partner and their families that Keith remain in Limerick for the weekend."

Earls had been chosen to fill the void left by O'Driscoll's championship-ending shoulder injury. The likely identity of O'Driscoll's replacement was the source of intense debate, but three days out from Ireland's Six Nations opener Kidney was forced into a rethink.

Earls, Ireland's leading try-scorer at last autumn's World Cup, offers more of an attacking threat than McFadden, though there are doubts over his hands and defence.

McFadden, who made his Test debut against Italy last year and is more accustomed to playing centre, is stronger in the tackle, but lacks Earls' gamebreaking ability.

Kearney insists McFadden will slot seamlessly into the line-up having been on standby ever since concerns over the health of Earls' baby arose.

"Fergus has obviously been training with us for the last couple of weeks," said Kearney. "When Keith missed a couple of days last week Fergus, filled in at outside centre."