South Africa produced an unconvincing performance with the bat but beat Zimbabwe by five wickets to set up a semi-final against New Zealand.
An 18-ball 42 from Dewald Brevis at number four proved crucial as wickets tumbled in South Africa’s chase of 154 before George Linde (30 off 21) and Tristan Stubbs (21 off 24) saw them over the line with 13 balls to spare.
South Africa, who have won all seven of their matches in this tournament, are searching for a maiden T20 World Cup title having previously reached the final in 2024.
The result also confirms England, who finished top of Group 2 in the Super 8s, will face either India or West Indies in the last four as neither side will be able to match South Africa’s haul of six points.
They meet in the final Super 8 game at 13:30 GMT, with the winner progressing to the semi-finals.
After restricting Zimbabwe to 153-7, South Africa lost three wickets inside the powerplay, with Sikandar Raza (3-29) removing openers Quinton de Kock and Aiden Markram for single-figure scores and Ryan Rickelton for 31 (22).
From 43-3, Brevis combined with David Miller (22 off 16) for a 50-run fourth-wicket stand off 25 balls to break the back of the chase before both batters fell in the space of five deliveries to set up a nervy finish with 53 runs needed from 56 balls.
Earlier, Zimbabwe captain Raza had proved a thorn in South Africa’s side with the bat, striking a defiant 73 (34), including eight fours and four sixes. Clive Madande (26 not out) was the next highest scorer, chipping in with a handful of late boundaries to take Zimbabwe beyond 150.
Teenage quick Kwena Maphaka was the pick of the bowlers, taking 2-21.