James Hook could miss Wales' summer tour to New Zealand, which features two Tests against the All Blacks.
Ospreys centre Hook, arguably Wales' star performer this season, requires shoulder surgery and Wales boss Warren Gatland must decide whether Hook should have his operation before the June tour or afterwards.
The recovery period is likely to be up to five months, and Gatland said: "James has had the problem for a while and he needs surgery."
He added: I talked with the Ospreys earlier in the season about whether it would be best for him to have the operation before the start of the Six Nations, but they wanted him to be available at the end of the season and I could understand that.
"He will be out of action for between three and five months, and we have to consider whether he should be operated on before or after the New Zealand tour.
"We and the Ospreys have had to manage him in terms of contact, and it is testament to him that he has had an excellent season."
Gatland, who plans to announce his tour squad around the middle of next month, has confirmed that Cardiff Blues centre Tom Shanklin is unavailable due to his recovery from knee surgery.
And the coach is also debating whether or not to rest Blues flanker Martyn Williams, but will otherwise take his strongest available squad to New Zealand.