Paul O'Connell in action against England in last year's Six Nations

The inspirational Munster player may be forced to undergo surgery to correct a prolapsed disc which has troubled him since the World Cup.

O'Connell completed an eight-week rehabilitation programme recently and made a comeback for his club but the problem reared up again in training.

A decision on whether immediate surgery is needed is expected within 48 hours.

The alternative for the second row forward is more rehabilitation.

If consultants advise surgery, it is likely he will miss the complete Six Nations campaign but officials hope he may ready for the final game against England at Twickenham on 15 March.

606: DEBATE How much of a blow would O'Connell's absence be to Ireland?

However, it is likely he will not be risked any further this season if surgery is required and his next match in Ireland's colours could be during the summer tour to New Zealand and Australia in June.

The news will come as a blow to Ireland coach Eddie O'Sullivan and his backroom staff whose future could depend on the team's performance in the Six Nations.

Ireland face Italy in their Six Nations opener at Croke Park on 2 February.