Wales have not ruled Tomas Francis out of the South Africa summer tour but insist his health will come first.
Prop Francis, 30, suffered a concussion almost immediately after coming on for Dillon Lewis during the second half of last Saturday's 32-29 loss in Pretoria.
Wales coach Wayne Pivac has confirmed Francis will miss the second South Africa Test in Bloemfontein on 9 July.
Wales will wait to see if the Ospreys player is fit for the third Test in Cape Town on 16 July.
"It is a minimum 12 days for him," said Wales forwards coach Jonathan Humphreys.
When asked whether Francis could still play a part in the third Test, Humphreys replied: "Hopefully but the priority is his health.
"We've got an unbelievable medical department making sure that he comes first.
"He's good. It was tough at the time, to see anybody be knocked out like that. He recovered well afterwards and he seems pretty good in himself.
"It's over to the medics to take it from now."
Francis suffered a head injury against England during the Six Nations in February 2022.
On that occasion, he temporarily left the field for an independent head injury assessment (HIA) before returning to play.
Wales were criticised for not replacing him permanently at the time and a Six Nations review later found Francis should have been "immediately and permanently removed from play" after his head injury.
New cap awaits
Francis had arrived in South Africa nursing a back injury and with Leon Brown and Samson Lee injured, uncapped tight-head props Sam Wainwright and Harri O'Connor are competing to deputise for Dillon Lewis.
Humphreys has dismissed the possibility of British and Irish loose-head Wyn Jones being asked to cover the other side of the scrum, a job he did during the 2019 World Cup.
"We've got two other tight-heads that we've brought out with us in Sam and Harri so it's a massive opportunity for either one of those," added Humphreys.
"It's a hell of an opportunity for anybody, especially two very committed young professionals like those two.
"It's a massive positive for them and for us because it increases our depth in that area and that's what we're after.
"I'm confident that they're ready to take on the occasion. They're extremely impressive young people and they've worked their socks off since they've been over here. They've fitted right in.
"I'm confident the occasion won't be too much for them and they'll go out there and give everything they've got."
Humphreys says Wales will bounce back from the disappointment of losing to the final kick of the game in Pretoria.
"Everybody is disappointed," added Humphreys.
"It was a good effort. We stuck largely to what we said we were going to do, especially in the first half.
"To lose in the last minute of any Test, especially this one at a full house in Loftus, is a tough one.
"It's not hard to pick yourselves up. We talked about that in the changing room afterwards and the big thing for us we have to be better than we were on Saturday.
"We have to improve if we are going to get what we want out of this tour. It is a lot of work we need to do and we are prepared to do that."