The Ospreys have suffered an injury setback with Scotland wing Nikki Walker having a knee operation.
He was only minutes away from making Scotland's World Cup squad when he suffered medial ligament damage against Italy.
He is on crutches with the region unable to set a target date for his return.
The Ospreys are likely to have World Cup stars Tommy Bowe and Shane Williams as their Heineken Cup first choices.
But Walker's long term absence is likely to mean more chances for the likes of young wingers Kristian Phillips and Hanno Dirksen.
Meanwhile, the region will have Samoan pair Kahn Fotuali'i and George Stowers and Canadian flanker Chauncey O'Toole in training next week.