South Africa qualified for the T20 World Cup Super Eights on Monday without playing as Afghanistan's win over the United Arab Emirates was enough to send them through from Group D.
Azmatullah Omarzai was the hero for Afghanistan, taking 4-15 in the UAE's 160 for nine and scoring an unbeaten 40 to steer his side to a five-wicket win after a tense chase in New Delhi.
Afghanistan finished on 162 for five with four balls to spare to keep alive their slim chances of moving into the next stage.
South Africa, finalists in 2024, became the third team after the West Indies and co-hosts India to secure a Super Eights berth.
Afghanistan will need a big win in their last group match against Canada on Thursday and other results to go their way if they are to edge out New Zealand from second place in Group C.
"Next game, you never know, it's a T20 game, we'll have to come up with a good brand of cricket, irrespective of the chances of making it to the Super Eights," said Afghanistan captain Rashid Khan.
"We want to make the country and our people proud and happy."
New Zealand can seal their spot and eliminate Afghanistan with a win against Canada on Tuesday in Chennai.
Sohaib Khan top-scored for UAE with 68 and put on a stand of 84 for the third wicket with Alishan Sharafu, who made 40.
Medium-pace bowler Muhammad Arfan dismissed Ibrahim Zadran in the 14th over to tilt the scales in the UAE's favour at 97 for four, but Darwish Rasooli and Omarzai put the chase back on track with a fifth-wicket partnership of 43.
Rasooli departed for 33 in the 18th over, but Omarzai kept calm and hit the winning four to give Afghanistan their first win of the tournament.