Kagiso Rabada tore through Australia to ensure South Africa will face Pakistan in the final of the Under-19 World Cup courtesy of an 80-run victory.
Clyde Fortuin and Aiden Markram made 74 and 45 respectively and set up the Proteas well with an opening stand of 105.
Australia’s spinners fought back in an impressive collective effort and South Africa might have been forgiven for thinking they were below par in posting 230 for nine.
They need not have worried as Australia lurched to 33 for three in the face of a fearsome opening burst from Rabada, during which the paceman touched speeds of 90mph.
He returned to dismantle the tail and finished with figures of 6-25, Australia all out for 150 in 42.2 overs.
There was a much more closely contested affair in the 13th-place play-off, where three wickets each for seamers Abdul Sabri and Nick Farrar edged Scotland past Namibia by five runs.
Set 179 to win, Namibia looked on course to fall comfortably short before Bredell Wessells and Kobus Brand combined to add 28 for the last wicket and fray Scottish nerves.
Their fun ended when Sabri removed Wessells with the score on 173.
Papua New Guinea would have been grateful for such lower-order resilience as they collapsed from 150 for six to 158 all out to hand Canada victory by 11 runs in the 15th-place play-off.
Canada suffered similar woes on their way to 169, with no batsman reaching double figures to compliment the fine work of Yug Rao and Stephan Joseph - the pair making respective scores of 77 and 58.