LEINSTER flanker Sean O'Brien will miss out on the first two rounds of the Heineken Cup and possibly Ireland's November internationals next season.
Carlow forward O'Brien will be out of action for anything up to four months with a hip injury that requires surgery.
"Seán is having some keyhole surgery on his hip to repair some cartilage damage within the next week or so, and the recovery for this type of operation is 13 to 15 weeks," said Ireland team manager Mick Kearney.
"It means it could be up to four months. Obviously it's going to make him doubtful for November. Like any operation there is some risk attached to it.
"But the medics feel he will make a full recovery and that he will certainly be back towards the end of October and he should be back playing Heineken Cup rounds three and four in December."
In the three Tests against New Zealand, O'Brien broke even with Richie McCaw in the first Test, outplayed him in the second before suffering an All Black backlash in the third.
He will join fellow back rower Rhys Ruddock and wing Dave Kearney, currently suffering from the same hip ailment.
Centre Eoin O'Malley is another in the long-term casualty ward as he recuperates from a broken ankle and knee injury.