The Proteas comfortably chased down a revised target of 127 to triumph by nine wickets on the Duckworth-Lewis-Stern method, and spy some light in what has been a very dark tunnel.
Beset by injuries and off-field issues, South Africa were staring at an early exit after three defeats and a no result in their first four games.
It was a situation unbefitting of a team third in the one-day international rankings and boasting the talents of Quinton De Kock, Kagiso Rabada and Imran Tahir.
Skipper Faf Du Plessis had said before their first ODI meeting with Afghanistan that nothing other than victories from their five remaining group games would do to secure a semi-final place.
Unlikely maybe, but South Africa are now in the same position as the Pakistan team that went on to win the 1992 tournament.
The first step on that path, in truth, was always going to be taken after Afghanistan’s extraordinary batting collapse on a pitch that was green and soft in parts.
Tahir led the way with four for 29 from seven overs, the veteran spinner’s sorcery bemusing a batting line-up frustrated by two rain delays.
Chris Morris (three for 13) and Andile Phehlukwayo (two for 18) assisted as Afghanistan, 69 for two at the second stoppage, promptly lost five wickets for eight runs in 29 balls.
Hazratullah Zazai (22) and Noor Ali Zadran (32) put on 39 for the opening wicket before Afghanistan’s familiar struggle to score in the middle overs.
Tahir claimed the prized scalp of Noor Ali with his first ball, bowling him through the gate, and held a return catch to dismiss Asghar Afghan with his fifth.
Excellent support in the field from Aiden Markram and Rassie Van Der Dussen gave him four wickets and 37 in World Cups, leaving Allan Donald (38) the only South African bowler ahead of him.
The only ray of light for Afghanistan came from Rashid Khan who, batting at nine, struck six fours to top score with 35 from 25 balls.
Afghanistan were dismissed for 125 in 34.1 overs and South Africa had the opportunity to reach their target quickly and significantly improve their net run rate.
Hashim Amla and Quinton De Kock started cautiously in the evening sunshine, but with little fright.
The much-vaunted Rashid produced turn and bounce, but De Kock reached his second 50 of the competition from 58 balls.
De Kock had moved on to 68 when he flicked Gulbadin to Nabi at mid-wicket.
But Amla (41 not out) and Phehlukwayo (17 not out) – who completed victory with the first six of the match – saw South Africa home with 19.2 overs to spare.
Afghanistan remain rooted to the bottom of the table, still looking for their first point ahead of an Old Trafford date with England on Tuesday.
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