By Lehlohonolo Lehana.

Australia fast bowlers Mitchell Starc and Josh Hazlewood took two wickets each to rip through South Africa's top order in the second World Cup semi-final on Thursday.

Left-arm quick Starc sent back skipper Temba Bavuma for a fourth-ball duck in the first over and soon Hazlewood had the in-form Quinton de Kock caught for three.

The new-ball bowlers kept up the attack with the wickets of Aiden Markram (10) and Heinrich Klaasen (10) to reduce South Africa to 44-4 in 14 overs after the Proteas elected to bat under cloudy skies and rain in the air.

For South Africa, spinner Tabraiz Shamsi came in for pacer Lungi Ngidi in their only change, while Australia went with Marnus Labuschagne and Starc in place of Marcus Stoinis and Sean Abbott in their playing XI.

Both teams ended with 14 points after seven wins from nine league games to make it to the knockout stage. 

South Africa are chasing their first ever World Cup final after faltering in four semi-finals including two against Australia in 1999 and 2007.

The winners of Thursday's game will take on undefeated hosts India, who knocked out New Zealand in the first semi-final, in Sunday's final at Ahmedabad.

South Africa: Temba Bavuma (captain), Quinton de Kock, Rassie van der Dussen, Aiden Markram, Heinrich Klaasen, David Miller, Marco Jansen, Kagiso Rabada, Keshav Maharaj, Lungi Ngidi, Tabraiz Shamsi.

Australia: David Warner, Travis Head, Mitchell Marsh, Steve Smith, Marnus Labuschagne, Josh Inglis, Glenn Maxwell, Pat Cummins, Mitchell Starc, Adam Zampa, Josh Hazlewood.