The South Africans thrashed England by 103 runs, while Australia got the better of Bangladesh by five wickets.
South Africa thrashed England by 103 runs to set up the ICC Under-19 World Cup semi-final with Australia at the Tony Ireland Stadium in Townsville on Sunday.
Chasing 245 to win, the English team was 101 for 1 at one time before skittling for 141 in 40.3 overs. Offspinner Prenelan Subrayen was the destroyer in chief with figures of 4 for 24. Lizaad Williams also chipped in with 2 for 23.
After being put into bat, the Proteas middle order batted with a lot of common sense to take the team to 244 all out in 50 overs. Murray Coetzee (67), Theunis de Bruyn (54) and Chad Bowes (46) played crucial hands.
Meanwhile, in another quarterfinal, Australia beat Bangladesh by five wickets with 25 balls to go at Endeavour Park No 2 in Townsville.
Chasing 172 for win, the Aussies were in a fix at one time at 33 for 4. But captain William Bosisto (71 not out) led from the front to take his team over the line. He was well supported by Travis Head (44) and Ashton Turner (27 not out) at the other end.
Earlier, Bangladesh displayed a poor batting show after being put into bat. Except Soumya Sarkar (73), the rest of the batsmen fared miserably as the subcontinental team was bowled out for 171 in 43 overs. Head was the pick of the Australian bowlers with 3 for 30. Turner and Joel Parris also took two wickets each.
Elsewhere, Scotland beat Zimbabwe in a 9th place play-off quarter-final at Peter Burge Oval in Brisbane. Chasing Scotland’s 241 for 7, the African team could only go as far as 200 for 9. Ryan Burl did his best with 52 but it wasn’t enough.
Earlier, after being put into bat, the Scotts rode on Nicholas Farrar (58) and Peter Ross (43) to post a formidable total.
And, Afghanistan saw off Papua New Guinea in another 9th place play-off quarter-final at Allan Border Field in Brisbane.
Chasing 240 to win, the Afghans got over the line in the 49th over with Mohibullah Paak (58 not out) and Afsar Khan (37 not out) adding 85 runs for the seventh wicket.
Papua New Guinea captain Christopher Kent unbeaten 105 went in vain.
South Africa 244 all out (Coetzee 67, de Bruyn 54, Topley 3-45)
England 141 all out (Davies 54, Foakes 54, Subrayen 4-24)
Bangladesh 171 all out (Soumya Sarkar 73, Travis Head 3-30)
Australia 172-5 (William Bosisto 71*, Taskin Ahmed 2-31)