Johannesburg - Stormers back Damian de Allende was forced to withdraw from the Springbok squad on Monday and will be replaced by Lions flyhalf Marnitz Boshoff.
De Allende, one of seven uncapped players in the Springbok squad, suffered a medial knee ligament injury in the Stormers' Super Rugby match against the Sharks in Durban on Saturday.
The 22-year-old centre was taken for scans by the Springboks' medical team on Monday morning and will be sidelined for between four and six weeks, ruling him out of the Incoming Series.
"This is a great setback for Damian and we're all very disappointed that he won't be available for the Springboks this month," said Springbok coach Heyneke Meyer.
"Damian has been in great form and I was giving serious consideration of using him during the Castle Lager Incoming Series.
"It would have been a special moment for him to make his Springbok debut in front of his home crowd at Newlands on Saturday. However, I'm sure he will be back and we wish him well with his recovery."
Meyer said Boshoff was one of the unlucky players to miss out on selection in the initial squad, which was named on Saturday evening.
"Despite already losing Jean de Villiers and Jaque Fourie to injury, we still have good depth in the midfield, which is why we've decided to call up Marnitz," said the Springbok coach.
"Everyone knows his goal-kicking is sublime, but I was very impressed with the way in which he controlled the game in the Lions' victory over the Vodacom Bulls last weekend."
Boshoff will join the camp in Cape Town on Tuesday morning.