The prop is back in Wales' starting line-up for the first time since the match against Ireland four months ago after being troubled by a calf injury.
Ben Evans has played at tighthead prop in the last five Tests - winning the lot, against France, Italy, England and the 2-0 series win in Argentina - but Young is one of two changes made from the side who beat the Pumas 23-16 in Buenos Aires earlier this month.
"It's very much a case of horses for courses," said the Wales coach, Graham Henry. "Ben has played exceptionally well in the last five Test matches and in fact he is unbeaten as a Welsh international. However, David has proved himself having come back from a calf injury and he deserves an opportunity. It's the same situation with Colin Charvis. He didn't play well in the first Test in Argentina and Geraint Lewis came in for the second Test. However, Colin is back in and he will be keen to make an impression."
With the World Cup squad named on Monday, the 22 on duty on Saturday will want to make sure of their places in a party of 30 players. There are unlikely to be any real surprises in that selection, but the captain, Rob Howley, said: "The boys may be a bit tired after the Argentina trip, but if you imagine what a place in the World Cup squad means to us, this game is very important. I am personally looking forward to playing in the Millennium Stadium."
WALES (v South Africa, Saturday, Cardiff): S Howarth (Sale); G Thomas (Cardiff), M Taylor (Swansea), A Bateman (Northampton), D James; N Jenkins (both Pontypridd), R Howley (Cardiff, capt); P Rogers (Newport), G Jenkins (Swansea), D Young, C Quinnell (both Cardiff), C Wyatt (Llanelli), C Charvis (Swansea), B Sinkinson (Neath), S Quinnell (Llanelli). Replacements: L Davies (Cardiff), S Jones (Llanelli), D Llewellyn (Ebbw Vale), M Voyle (Llanelli), B Evans (Swansea), A Lewis, J Humphreys (both Cardiff).Reuse content