Newport Gwent Dragons wing Will Harries will be out of action for six months after rupturing knee ligaments.
The 23-year-old Wales player suffered the injury during the Dragons' 32-28 victory over the Ospreys on 15 April.
The Dragons are pursuing a second opinion but are resigned to losing Harries for a substantial period of time.
"We are unlikely to see him before the New Year," said Dragons coach Darren Edwards.
"He's ruptured his knee ligaments and, though he's having a second opinion, it's a serious injury.
"It's a huge blow for Will and for us. It will affect our recruitment now. Our firepower is diminishing so we've got to have a look at things."
Harries joined the Dragons in June 2009 following his release from Northampton and also spent time on loan at Bedford Blues.
He won the first of his two caps for Wales as a replacement during the second Test against New Zealand in Hamilton last summer.