South Africa were dealt a major blow on Monday with the news experienced flanker Schalk Burger and rookie centre Juan de Jongh have been ruled out of the Grand Slam tour of Britain and Ireland.
Scans revealed that Burger, capped 63 times for the Springboks, has a broken rib, while De Jongh has suffered a hairline fracture to his left ankle.
Centre Adrian Jacobs, who was added to the squad as a precautionary measure on Sunday when it was discovered that another midfielder, Jean de Villiers, had a groin problem, is now named as a replacement. Burger's place goes to the Bulls forward Deon Stegmann.
Another player from the Pretoria franchise, full-back Zane Kirchner, has also been added to the 30-man list following the withdrawal of scrum-half Ricky Januarie.
The world champions begin their tour with a clash against the Irish in Dublin on Saturday, and coach Peter de Villiers said: "It's a blow to lose players but we've rolled with the punch and already moved on.
"We trained without them on Monday morning and we already had contingency plans in mind which we've begun to put into operation.
"It's not an ideal situation but we've all got on with our jobs and are focused only on the players that we have in camp."
The latest withdrawals take to 13 the number of senior players who have been forced out of the tour by injury.
The others that are unfit are captain John Smit, Jaque Fourie, Wynand Olivier, Andries Bekker, Fourie du Preez, Heinrich Brussow, JP Pietersen, Gurthro Steenkamp, Butch James and BJ Botha.