Dominic Adiyiah's stunning strike puts Ghana through to the quarter-finals of the FIFA U-20 World Cup.
Ghana had to rally from a goal down to defeat the Amajita's 2-1 in Ismailia.
The win sets up a clash with South Korea in Suez on Friday.
After a goalless first half, Andre Ayew drew Ghana level in the 66th minute after the South Africans had taken the lead on 58 minutes through Kermit Erasmus.
With both sides failing to find the winner in 90 minutes, the game went into extra time and it was Adiyiah who drove in a wonderful shot nine minutes into the first half of the last 30 minutes.
Ghana goalkeeper Daniel Agyei was in great form, saving goal attempts by Kermit Erasmus and Sibusiso Khumalo.
Agyei's fine form saw him tip Serero's curling free-kick over the bar and then denied Doutie with another save from a dipping shot from the right flank and was quick off his line to save bravely at the forward's feet.
After near misses, Erasmus scored when he brilliantly controlled Khumalo's quick free-kick, rounded the keeper and slotted home.
Ghana went in search for the equaliser and seven minutes after the opener, Ayew was hand to nod in David Addy's freekick.
John Benson was handed his debut at the competition as Ghana made a first change when he came on for Gladson Awako.
Before the final whistle could go, the Black Satellites bench replaced Ransford Osei with Opoku Agyemang.
Agyemang's introduction upped the pressure on the Amajitas, but it was Adiyiah who settled matters.
After receiving the ball from Addy, Adiyiah with his back to goal turned sharply and fired the ball high into the net from 25 yards.
With Ghana in the lead, South Africa were given some added boost after the sending off of Agyemang for a second bookable offence.
Despite the sending off, Ghana held on firmly to finish the tie winners.
line up: Daniel Agyei, Samuel Inkoom, David Addy, Jonathan Mensah, Daniel Addo, Agyemang Badu, Abeiku Quansah, Gladson Awako/John Benson, Dominic Adiyiah, Ransford Osei/Opoku Agyemang, Andre Ayew
Subs: Opoku Agyemang, Latif Salifu, Kassenu Ghandi, Daniel Opare, Philip Boampong, Robert Dabuo, John Benson, Bright Addae, Joseph Addo