Wales will be without Perpignan lock Luke Charteris when they face Australia in Cardiff on 30 November.
The game falls outside the autumn Tests window and Charteris, Wales' man-of-the-match in their will be on club duty in France.
Fellow Perpignan star James Hook and Bath prop Paul James will also miss the Wallabies Test.
Wales coach Warren Gatland confirmed the absences as he reflected on their "ugly" win over Tonga.
"Luke Charteris and James Hook are going back and so is Paul James," said Gatland.
"But as far as I know everyone else is available."
Confirmation of Charteris' absence came despite the player stating in March 2012 that he had secured his release for all Wales duties before moving to the Top 14 French club.
But while prop James must also return to his Aviva Premiership club for next weekend, wing George North will line up against Australia, not Northampton at Worcester on the same day.
With Cardiff Blue Bradley Davies having been ruled out by shoulder surgery and Charteris unavailable, Gatland's lock options are limited for the Australia Test.
British and Irish Lions Alun Wyn Jones and Ian Evans, both Ospreys players, seem likely to start against the Wallabies.
Newport Gwent Dragons skipper Andrew Coombs and Ryan Jones, the Osprey who led Wales from number eight against the Sea Eagles, could also be lock contenders.
But Coombs was originally picked at flanker against the South Sea Islanders only to fall victim to a ahead of kick-off.
Ryan Jones is the more likely lock back-up to face Australia.
Gatland hopes Wales will be more clinical against their next opponents having seen his side fail to build on a 17-0 lead established by the 25th minute of their clash against Tonga.
Well-worked and taken tries by Owen Williams and Ashley Beck underlined Wales' attacking potential.
But after Will Helu's response for the visitors, defences reigned.
"To be fair to Tonga, they frustrated us," said Gatland after his 100th Test as a coach.
"I think there was 11 minutes ball in play in first half, which for me was probably the lowest I've ever seen in an international game in a first half.
"And that was kind of the way it was played; re-set after re-set and slowing the game down and stopping. And that made it difficult for us to get some momentum."
The New Zealander added: "It's an ugly win, but we'll take it. It's frustrating, but there was the ambition there to go and play and put ourselves under pressure to play.
"We need to be better and more clinical next week, but with some youngsters who hadn't had a chance, players who haven't played a lot in the last few years, I was pleased for them to come in and experience that and for us the win was ultimately the most important thing."
Gatland also said "no injuries" were "a real positive" for Wales amid an autumn series that has seen them lose lock Davies, prop Adam Jones (calf), centres Jonathan Davies (pectoral) and Cory Allen (shoulder) and wing Alex Cuthbert (ankle).
Wales also went into November without Davies' fellow Lions centre Jamie Roberts (ankle).
However, Gatland was pleased with the contributions of one rising talent and one of Wales' established backs - wing debutant Hallam Amos and experienced full-back Leigh Halfpenny.
"Hallam Amos had a good game for us. Leigh Halfpenny, in the second-half, started to run to run pretty well."
Gatland said Tonga "didn't create a lot", adding: "Defensively we were strong and particularly in that second-half, even though out of the 27 turnovers we made I think 24 of them were in their half.
"So that's too many for us. We need to be better and more clinical than that for next week."