Jamie Roberts admits the injuries suffered by Leigh Halfpenny and Rhys Webb are a "huge blow" to Wales' World Cup hopes.
Full-back Halfpenny and scrum-half Webb, two of Wales' finest players, suffered knee and ankle ligament injuries respectively in Saturday's 23-19 defeat of Italy and were stretchered off at the Millennium Stadium in Cardiff.
The Welsh Rugby Union announced on Monday that Halfpenny damaged his anterior cruciate ligament and will miss the tournament, while Webb's status is still unknown.
Wales have been drawn in an extremely difficult Pool A which also contains England and Australia and 28-year-old centre Roberts admits the loss of Halfpenny and potential loss of Webb are crushing blows to the team so close to the tournament.
"It's a blow, there's no doubting that," said Roberts. "They're two quality players, two first-team players. It's a huge blow.
"The qualities of both of them shouldn't be under-estimated. They're two quality lads who bring a lot to the team and the squad environment. The timing of this one is desperately unfortunate.
"They were quite nasty. They looked in a lot of pain.
"It's a big blow - two wonderful players, first-team players, who've been instrumental in our success in the past few years. It's difficult. It'll test our strength in depth, but this is why Warren [Gatland] has bred strength in depth in the past few years. We have to be ready for moments like this."
Former Wales winger Shane Williams questioned Gatland's decision to leave Halfpenny on the pitch against Italy but Roberts feels that criticism is unfair.
"Warm-up games are important, for the lads to get up to match fitness," Roberts said. "These injuries can happen in training, and can happen in games.
"Hindsight's a wonderful thing. If we beat Italy by 60 points at the weekend with a clean bill of health, it's a great exercise, so what can you say? It's very easy to make comments like [Williams'] after.
"The changing room was a quiet place, first of all because of the performance.
"Yes, we did get some things right, but there were a lot of things that didn't go as well as we'd hoped. And secondly the injuries, because we're all quite close, seeing good mates get injured is never nice."