Ross Cronjé will join up with the Springboks after Toulouse turned down a request for Jano Vermaak to be released for the match against Wales in Cardiff.
Cronjé will join the squad as a replacement for Rudy Paige, who suffered an ankle injury in training earlier this week, ruling him out of action for four weeks.
Vermaak had been part of the squad for the first three November Tests, but had to return to France this week as the Test against Wales falls outside of the official Test window. Despite requests from Saru for his services, he will turn out for Toulouse in the Top 14 this weekend.
For Cronjé it's his first involvement with the senior squad, having been part of the Junior Boks squad at the 2009 Junior World Championship.
'Ross impressed during a very successful Currie Cup campaign for the Golden Lions and also showed good form earlier in the year in Super Rugby,' said Springbok coach Heyneke Meyer on Cronjé's selection. 'We considered not calling up a third scrumhalf but that would've been very risky.'
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