Cardiff flanker James Botham will miss the opening months of the season and is a major doubt to play any part in Wales’ autumn international series after undergoing shoulder surgery.
The 23-year-old is targeting a return to action in November with Wales hosting New Zealand on 30 October.
That is followed by matches against South Africa, Fiji and Australia.
British and Irish Lions duo Josh Adams and Josh Navidi are due to return to training for Cardiff in two weeks.
The pair will not be involved for Cardiff until at least the third game of the season and will play only one or two matches before Wales begin their autumn campaign.
Wales are already missing injured Ospreys openside Justin Tipuric for the autumn fixtures.
Cardiff begin their United Rugby Championship season against Connacht on Friday, 24 September after pre-season matches at Harlequins on Saturday, 4 September before hosting Bath six days later.
Botham’s surgery took place in early August and he is Cardiff’s only new significant injury ahead of the 2021-22 season with fly-half Luke Scully and utility back Mason Grady continuing their recoveries from knee ligament injuries.
Lock Ben Murphy (knee) and Wales centre Ben Thomas (groin) are currently unavailable, but Cardiff say they are on track to return during the opening rounds of the season.