Ospreys trio Huw Bennett, Andy Lloyd and Luke Tait will all miss the start of the Celtic League campaign against Munster this weekend.
Wales hooker Bennett, who toured Argentina and South Africa in the summer, is suffering a hernia and could also miss the west Wales derby against Llanelli a week later.
Flanker Lloyd is also out for a fortnight with a hamstring problem while coach Lyn Jones is also keeping a close eye on lock Tait's neck strain.
'It's a blow but we have brought in a number of high-quality players to strength in depth to the the squad,' said Jones.
Meanwhile the Ospreys are considering a change in team name and playing colours for next season as they quiz supporters from Neath and Swansea over the future of the regional team.
Ospreys chief executive Andrew Donald said: 'The consultation will be exactly that - a listening exercise. We want to know from supporters what they think we've got right and where we could do better. We'll want to know what they think of the Ospreys' identity and branding, as well as obtain feedback on the Ospreys' future facilities.'
As the countdown continues for RWC2015, Tournament Chief Executive Debbie Jevans visited the Millennium Stadium to discuss preparations for the eight matches and reveal the positive news that 100,000 tickets for games at the home of Welsh rugby have sold in the last seven days.
Jason Harries is targeting a first win on the World Series circuit this season with Wales. The series returns to action this weekend in Dubai where Harries is part of a team hoping to build from its efforts in round one in October.
Wales skipper Jevon Groves says his side have addressed a few points from Gold Coast and aim to 'hit the ground running' in the next two rounds of the World Series, kicking off with this weekend in Dubai before heading off to South Africa next week.
Wales Sevens manager Steff Thomas is hopeful his side can build from a quarter-final spot in the opening round of the World Series in Australia when his side take part in the forthcoming double header in Dubai and South Africa.