SEAN O’BRIEN WILL now miss the start of Ireland’s Six Nations campaign after Leinster this afternoon confirmed the flanker has had a small procedure to resolve an ongoing hip issue.

The 30-year-old has been sidelined since Leinster’s Champions Cup win over Exeter Chiefs at the Aviva Stadium at the start of December, but had insisted he wasn’t an injury concern for the Six Nations, which gets underway on 3 February.

However, the tightness in his hip has failed to respond to treatment and O’Brien met with a specialist earlier in the week before it was decided going under the knife was the best course of action.

Leinster say the target is to have O’Brien back available ‘during the Six Nations window’, which has raised further doubts over whether he’ll be fit to play any part during the championship.

O’Brien will almost definitely miss the opening two rounds against France and Italy but the break between the visit of Conor O’Shea’s side to Dublin and Ireland’s clash with Wales on 24 February may give the Lion time to recover.

During that period, Leinster have Guinness Pro14 games against Edinburgh, Scarlets and the Kings.

Meanwhile, Adam Byrne’s comeback from a knee injury has received another setback after it was confirmed the winger will have a procedure today in a bid to repair the damage.

Leinster say a return to play timeline for Byrne, who hasn’t played since making his international debut against Argentina in November, will be formalised post-surgery.

Leo Cullen will likely provide further updates on both players when he speaks to the media later this afternoon.

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