Sri Lanka have collapsed inside three days as South Africa have swept their Test series 2-0.
Batting a second time in the game, Sri Lanka made 211 all out despite a solid 103 from 128 balls by Dimuth Karunaratne.
Only three other batsmen managed to get past double figures.
Lungi Ngidi led the bowling attack with 4/44 while Lutho Sipamla took three, Anrich Nortje grabbed two and Wiaan Mulder took one wicket.
Their 211, in addition to their 157, meant Sri Lanka only had a 66-run lead over their opponents who made 302 in their first innings.
South Africa’s openers, Aiden Markram (36 not out) and Dean Elger (31 not out), ensured the Proteas knocked off their target without losing a wicket.
Elger was named Player of the Series following his innings of 95 in the Boxing Day Test and 127 in the first innings of the second fixture.
South Africa won the first Test by an innings and 45 runs.