Ospreys scrum-half Rhys Webb has had minor shoulder surgery, but is expected to be fit for the start of the 2011-12 season.
Webb overtook Wales and British and Irish Lions scrum-half Mike Phillips in the Ospreys' pecking order last season, making 18 starts in 21 appearances.
Prop Craig Cross has also undergone surgery, in his case to a knee.
Opsreys physiotherapist Chris Towers expects both players to be fit for next term.
"We expect that Rhys will be kept out of full contact for a period of 12 to 14 weeks," said Towers.
"We don't see this impacting too much on his pre-season preparations in terms of his physical work, and as such, we are hopeful that he will be available for selection at the start of the season.
"Craig will continue his rehab over the summer break, before undergoing what we expect will be a modified pre-season programme and we would expect that he will come good in time for the start of the season."