Wales back-row forward Ross Moriarty will undergo surgery to release pressure on a nerve injury that has sidelined him for six weeks.
And it could make the 54 times-capped Dragons player a doubt for Wales’ South Africa tour in July.
Moriarty was carried off – his left leg in a brace – after being hurt during Dragons’ United Rugby Championship game against the Sharks in Durban.
“Ross is going to have surgery to try and release the pressure he has on his nerve,” Dragons rugby director Dean Ryan told the region’s official website.
“Everybody is working around that to see what the timelines are, so we have gone through a period of trying to rehabilitate that.
“It hit a bit of a stalemate, so we are hoping the next move is a way of accelerating his progress. I would be always hopeful his recovery is fast, so we will see how that goes.”
Moriarty’s Dragons and Wales colleague Aaron Wainwright, meanwhile, is set to be ruled out of summer tour contention after suffering a fractured heel.
Wales head coach Wayne Pivac is due to name his squad next week for Tests against the Springboks in Pretoria on July 2, Bloemfontein seven days later and then Cape Town on July 16.
Absentees are likely to include British and Irish Lions trio Leigh Halfpenny, Ken Owens and Justin Tipuric, who are all sidelined because of long-term injuries.