Giant Springbok lock Eben Etzebeth is expected to be sidelined for up to 10 days with a shoulder injury, South Africa's director of rugby Rassie Erasmus said on Monday.
Etzebeth left the field in the 26th minute of the 18-3 victory over Scotland in Marseille on Sunday in both teams' Pool B opener.
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"We're waiting for the scan," said Erasmus. "I'm sure we'll have 100 percent clarity later this evening.
"It will still be a blow not to have him train for seven to 10 days."
South Africa continue the defence of their World Cup title against Romania in Bordeaux on Sunday, but Erasmus said Etzebeth "would always not be picked" for that game anyway.
"But we would have expected him to have trained fully."
Etzebeth started at lock alongside Franco Mostert against the Scots and was replaced by RG Snyman.
Meanwhile, Springbok coach Jacques Nienaber has bluntly hit back at criticism of Manie Libbok after he missed two penalties and a conversion in their 18-3 win over Scotland.
"Not if he wins man of the match," was Springbok coach Jacques Nienaber's blunt response to whether he had any concern over Libbok's missed kicks.
Libbok, 26, won that award after taking control in the second half of a gritty forwards-based match in Marseille and coming up with one particular piece of magic for the Boks' second try that effectively sealed the win.
The Stormers fly-half produced a perfectly-judged, no-look cross-kick to Kurt-Lee Arendse, the winger catching the ball in full flight and speeding away for a try that Faf de Klerk, having taken over the kicking duties from Libbok, duly converted from the touchline.
Springbok skipper Siya Kolisi was quick to defend Libbok.
"This question about missing kicks gets asked a lot," he said.
"We play as a team and sometimes you’re not good at one thing on the day.
"But the way Manie attacked, the way he took control of the team, how he was a general, people forget that and they remember" the missed kicks.
