Ospreys forward Ryan Jones is reportedly expected to be sidelined for Friday's Pro12 clash against Ulster due to a calf strain.
The 32-year-old's start to the season has been plagued with injuries, and the former Wales captain was hopeful of returning to the fold this week.
However, it has emerged that Jones has picked up a calf strain in training, putting him in doubt for Friday's encounter, according to BBC Sport.
Jones has made just one appearance so far this season.