DRAGONS full-back Will Talbot-Davies faces a lengthy lay-off after dislocating his right wrist in the derby win against the Ospreys.

The 22-year-old was forced off in the second half of the Guinness PRO14 success at Rodney Parade and will now target a return in the run-in.

The loss of Talbot-Davies is another blow in the back three for the region with Jordan Williams (knee) and Dafydd Howells (elbow) likely to be out for the rest of the campaign.

Owen Jenkins has undergone ankle surgery and will be out for between six and eight weeks.

Wales Sevens international Talbot-Davies had waited patiently for his chance at his specialist position of full-back and had grown through six successive starts at 15.

South Wales Argus:

"It's unfortunate because Will had been playing really well," said backs coach Barry Maddocks. "He stepped up strongly with Jordan out and it will be a loss because of the form he was in."

Wing Ashton Hewitt missed the win against the Ospreys because of a calf niggle but should be fine for Saturday's European Challenge Cup clash against Castres.

Jacob Botica, a fly-half by trade, is in line for his first professional start at full-back in France while Jared Rosser is set to be on the right wing.

That would mean that 20-year-old Rio Dyer, who scored the late leveller against the Ospreys and was named as official man of the match, misses out on the XV.

South Wales Argus:

"Jacob did pretty well when he came on (against the Ospreys) while we have got another youngster in Carwyn Penny who could be in the mix (at full-back)," said Maddocks.

"Rio has been in the mix and training with us for the last couple of years, he made his PRO14 debut before and did exceptionally well on the weekend.

"What he has got is sheer pace, is a strong runner and is a good listener who wants to get better."

Wales forward Cory Hill has recovered from illness and is likely to bolster the pack for the tussle with Castres' hefty forwards.

Boss Dean Ryan has to weigh up fielding him at blindside, where he played against Worcester and the Scarlets, or at his specialist position of lock.

Against Cardiff Blues and the Ospreys the Dragons fielded a back row trio of Wales internationals Aaron Wainwright and Ross Moriarty along with Taine Basham, who scored a hat-trick against Castres in October.

The region head into round five on top of Pool One and within touching distance of the quarter-finals.

Victory in Castres – something that no team has managed in Europe in four years – would secure a place in the last eight as group winners while even a losing or four-try bonus would be welcome.

That combined with a Leicester win against Cardiff Blues at Welford Road on Sunday would guarantee a place in the quarters.

Even if the Dragons fall to defeat in Castres they would claim top spot on final weekend if they beat Enisei-STM in Newport and the French side lose in Worcester.