George North remains a doubt for Wales' first Test against South Africa.
The Northampton wing has been selected in the starting XV for Saturday's clash in Durban, despite being laid low by a virus.
The illness saw North withdrawn from the squad which beat the Eastern Province Kings on Tuesday, but head coach Warren Gatland had been confident of having his star man fit for the weekend.
However, the Kiwi admits the 22-year-old is facing a battle to come through in time.
He said: "George felt a bit nauseous on Tuesday and he has unfortunately had a bit of diarrhoea and stuff, so he has been in his room and had food taken up to him.
"He is making slow progress but we will make a decision on him on Friday, or even later."
Wales may have to call on uncapped Scarlets winger Jordan Williams to replace North, although there is also the option of moving Liam Williams from full-back and bringing James Hook or Matthew Morgan into the number 15 jersey.
There are two changes from the side which hammered Scotland at the end of the Six Nations.
Scarlets flanker Aaron Shingler fills the number seven shirt with Sam Warburton and Justin Tipuric injured, while Adam Jones makes his 100th Test appearance on the tighthead side of the scrum.
Jones will be joined by fellow front-row stalwart Gethin Jenkins, who wins his 106th Welsh cap, in an area which could prove critical to the outcome at Kings Park.
Saturday's referee, Frenchman Romain Poite, sin-binned Jenkins during Wales' Six Nations defeat to England at Twickenham.
But Gatland is expecting no repeat this weekend.
He said: "It was not difficult selecting Gethin. The England game was the only one he was penalised in and we feel the new scrum call system really suits him. He has been scrummaging really well.
"We spoke to Romain and (International Rugby Board referees' chief) Joel Jutge after the Six Nations because the last thing we want is scrums to be a mess because we feel we have a reasonable amount of firepower behind that and we can play off it.
"We just needed some clarity and we feel pretty comfortable at the moment. We will catch up with the referee on Friday just to get his thoughts on it as well."
One area of apparent strength for Wales is at centre where the Lions pair of Jamie Roberts and Jonathan Davies, who have 95 caps between them, face off against Jan Serfontein and JP Pietersen, neither of whom have started a Test match at centre.
But Gatland said: "Even though they have a few key players who are injured in the midfield, they still have the experience of someone like Pietersen.
"He has not played there much for his club but he knows the Test game, and then they have a young guy like Serfontein who has been playing well.
"We have a settled team with experience and we are looking forward to a good match, but we know whoever wears those green jerseys they are always tough to beat."