South Africa imposed the follow-on after bowling out Pakistan for 194 to take a 421-run first innings lead on the third day of the second Test at Newlands on Sunday.
Pakistan collapsed after a fourth-wicket partnership of 98 between Babar Azam (58) and Mohammad Rizwan (46).
Debutant Kwena Maphaka, 18, broke the stand five balls into the morning drinks break when Babar was caught behind by Kyle Verreynne, flicking the ball down the leg side.
Rizwan followed five overs later when he charged down the field against Wiaan Mulder and savagely hit his stumps.
Pakistan were without injured opening batsman Saim Ayub and there was minimal resistance from the rest of the batting order.
On Saturday, makeshift opener Ryan Rickelton posted the joint-seventh highest score by a South African in Test cricket with 259 to help his team reach a massive 566 for seven at tea on the second day of the Test.
The left-hander was dismissed 10 minutes before the break after hitting 29 fours and three sixes in a 343-ball stay at the wicket that put his team firmly in control of the match.
South Africa qualified for the final of the World Test Championship with a dramatic two-wicket victory over Pakistan in the first Test at Centurion’s SuperSport Park on December 29.
The Test had an ending more like that of a Twenty20 match, as the finalists achieved success after South Africa fell dramatically before lunch and offered Pakistan the chance to win a Test in South Africa for the first time in 18 years.