Pietersen, with 63 caps next to his name, is the only change made by coach Heyneke Meyer from the side which brushed aside USA 64-0 in the Springboks final pool game at the Olympic Stadium.
A knee injury forced Piertersen out of the USA game. His return means Bryan Habana will switch sides in what will be the 42nd time the pair have been a wing combination.
Habana currently leads the try-scoring stakes at the World Cup with five, while Pietersen is joint second with four, a position he shares with five other players.
“JP and Bryan have been in superb form and are playing some of the best rugby of their lives,” said Springbok coach Heyneke Meyer.
“They have been scoring some wonderful tries, as has Lwazi Mvovo, so it’s really great to know that there is good competition among the wings.
“It made sense to reunite Bryan and JP on the wing as it brings a lot of experience to our backline, which has been doing well despite the relative inexperience of Handré Pollard, Damian De Allende and Jesse Kriel.”
Meyer said his side have responded well after suffering the indignity of a humiliiating defeat to Japan in their opening game of the World Cup.
“It’s not easy when you come to the World Cup and from the first game you have to win every single match.
I think it helped us. You also have to respect your opponent as well,” explained Meyer.
“Wale have also been under huge pressure in their pool. It’s probably the same for both teams, probably a little bit more for us. The one thing we sorted out is the way we want to play. With all the experience back, all the guys we wanted right from the start back, and slightly hitting form, I’m happy that our last 10 tries were through our wingers.
“We’ve scored some great maul tries and I’m really happy with our defence because Wales are really going to test our defence. You have to have discipline on Saturday.”
The only player who was not considered because of injury was Victor Matfield.
South Africa team to play Wales
W le Roux; JP Pietersen, J Kriel, D de Allende, B Habana; H Pollard, F du Preez (capt); T Mtawarira, B du Plessis, F Malherbe, E Etzebeth, L de Jager, F Louw, S Burger, D Vermeulen.
Replacements A Strauss, T Nyakane, J du Plessis, PS du Toit, W Alberts, R Pienaar, P Lambie, J Serfontein.
