Gatland’s four changes from the Australia drubbing became six before kick-off with the loss of two of his better performers, prop Gareth Thomas (illness) and wing Tom Rogers (calf).
But this was still the most inexperienced Wales team in seven years with a meagre combined total of just 214 caps.
By comparison the Springboks second-row pairing of Etzebeth and Mostert have 207 between them and, as if to ram home the point, it was that pair who opened the scoring.
Both were gifted clear 20-metre runs to the line, Mostert from his perfectly timed run into Hendrikse’s pass, Etzebeth from a counter-ruck after Sam Costelow’s catch.
For the third week in a row, a Wales player limped off inside 10 minutes as Costelow made way, prompting a midfield shift that was horribly exposed for South Africa’s third try by Arendse.
Dominance at the scrum set up Louw for the fourth before Wales finally responded with a rare spell of possession on the stroke of half-time.
Having banged on a closed door up front for some four minutes, eventually it was simply the sheer pace of Dyer that got them over.
It was reminiscent of the days of Shane Williams – when all else fails, give it to the pacey wing.
Freddie Thomas won his Test debut after the break, the 15th new cap this year under Gatland, and there was at least some fight from the hosts.
But South Africa are world number one, the double world champions and the reigning Rugby Championship winners and wrapped up their first clean sweep of an autumn tour since 2013.
They were not convincing in the second half, but they did not need to be because they are so far ahead of the rest, especially Wales.
Gatland will try to fight on, but the next week could decide if he will be the man to lead them to the Six Nations.
