The Springboks are bracing themselves for 80 minutes of Welsh passion in their final match of the season, says hooker Johan Grobbelaar.
New Zealand closed their season with a commanding 52-26 victory over Wales in Cardiff on Saturday, stretching their remarkable winning streak in the fixture to 34 matches.
A dislocated shoulder picked up in the Test against Argentina over the weekend has ruled Wales star player and captain Jac Morgan out of action for about a month.
England delivered their most dominant performance of the season with a crushing 68-14 win over Wales in Cardiff on Saturday.
Wales flanker Taine Plumtree will adopt a "nothing to lose" approach as he prepares for his Test match return against the Springboks on Saturday.
Wales suffered the ignominy of a first Six Nations wooden spoon since 2003 after Italy posted a 24-21 victory over them in Cardiff.