Munster confirmed that Ireland second row Paul O’Connell will undergo surgery on his back injury at the earliest opportunity.

O’Connell has not played since their Heineken Cup win over Edinburgh at Thomond Park in October.

He is now likely to miss the Six Nations and his chances of going on next summer's Lions tour to Australia are in doubt.

But his Munster team-mates handed Ulster their first defeat of the season in the Rabo Direct Pro-12 last night.

They beat the league leaders 24 - 10 at Thomond Park.

Meanwhile at the RDS, Leinster picked up their first win in four games with a 17-0 victory over Connacht.

Image by ©INPHO/Dan Sheridan