Zimbabwe must win the match with a bonus point and also overturn a significant net run rate deficit if they are to join Australia in Saturday's final, and captain Elton Chigumbura confirmed that they would be targeting the huge victory required to do that.
The hosts made two changes to the side that stunned Australia on Sunday, leaving out opening batsman Tino Mawoyo and seamer Donald Tiripano.
Neville Madziva was drafted in to replace Tiripano, while Vusi Sibanda also earned a recall.
The Proteas also made two changes, one of which was injury-enforced after a scan revealed that all rounder Ryan McLaren had suffered a hairline fracture to his right arm after taking a blow from Australia paceman Mitchell Johnson on Tuesday.
With McLaren ruled out of the remainder of the tournament, Wayne Parnell returned to the Proteas side while Rilee Rossouw replaced Imran Tahir to beef up the batting department.
Teams
Zimbabwe: Sikandar Raza Butt, Vusi Sibanda, Hamilton Masakadza, Brendan Taylor (wk), Sean WIlliams, Elton Chigumbura (capt), Malcolm Waller, Neville Madziva, Prosper Utseya, John Nyumbu, Tendai Chatara.
South Africa: Quinton de Kock (wk), Hashim Amla, Faf du Plessis, Rilee Rossouw, AB de Villiers (capt), JP Duminy, David Miller, Wayne Parnell, Dale Steyn, Aaron Phangiso, Morne Morkel.