Cardiff - Wales and Scarlets centre Jonathan Davies has been ruled out for up to six months after suffering a foot injury.
Davies sustained the injury during Wales' 29-21 loss to Australia on Saturday and will miss his country's remaining Tests against Georgia, New Zealand and South Africa.
Davies, who has 65 caps for Wales, will need surgery and will likely also be sidelined for next year's Six Nations tournament.
"Jonathan Davies will undergo surgery to his foot following the injury sustained against Australia in the Under Armour Series," a Welsh Rugby Union statement read.
"It is envisaged that recovery will be in the region of six months."
It is a major blow for Wales and the Scarlets to lose Davies, who was British and Irish Lions player of the series against New Zealand earlier this year.
He went off during the final moments of Wales' 13th successive defeat against the Wallabies.
Although Wales head coach Warren Gatland is set to make several changes for next Saturday's meeting with Georgia, Davies was an integral part of his autumn plans.
The 29-year-old missed the 2015 World Cup due to a knee ligament injury, but he has been in world-class form throughout this year.
Shaun Edwards, Wales assistant coach and defence specialist Edwards, admitted it was a major blow to lose Davies.
"Obviously, I am incredibly upset for the player He is probably one of the form 13s, if not the form 13, in world rugby. He is going to take some replacing," Edwards said.
"He is a massive loss, there is no doubt about that. They are big shoes to fill. I have got a lot of work to do in the next three weeks and through the Six Nations.
"I am not saying he is irreplaceable, but it (13) would definitely be one of the positions you would least want to lose.
"It's unbelievably disappointing. But it's just the way it goes sometimes. We have to show a bit of resilience that we have shown in the past.
"I am sure there will be players who will put their hand up to play 13. We will just have to look at it over the next three games, and obviously the Six Nations."
Harlequins centre Jamie Roberts was called into Wales' autumn Test squad as injury cover on Monday.
Roberts, who has won 93 caps, missed out on a place in the original 36-man party announced by Gatland last month.