Nine minutes into day three, Sri Lanka's head coach was on the balcony, on his feet and applauding Dimuth Karnaratne's tenth Test ton. Thirteen minutes later, Arthur had his head buried in his hands probably aware that the knockout punch has been landed by South Africa. Karnaratne made 103 before Sri Lanka folded for 211 to set the hosts a target of 67 in order to gain a 2-0 series win.
The day started pretty positively for Sri Lanka as their captain struck two consecutive fours to reach his century off 123 balls. However, his dismissal was a few balls in the making. He had been tested with short balls and had fended at them awkwardly before he decided to take one on. The top edge was caught by Wiaan Mulder at square leg with the Sri Lanka captain falling after a commanding ton.
The opening wicket on the day was all South Africa needed to gain the ascendancy. The flick from Niroshan Dickwella went straight to Temba Bavuma at mid-off. Wanindu Hasaranga offered some resistance when he scored 16 off 32 but there wasn't much he could have done. The lower order crumbled under the continuous assault from Ngidi and Lutho Sipamla. From being 176 for 4, Sri Lanka lost their final six wickets for 35 runs.
Aiden Markram started the chase with a boundary on the first ball and continued to score freely. Lunch was taken with the hosts still 43 away but there was drama in the final over of the opening session. Markram drove away from the body and edged the away going delivery from Vishwa Fernando.
Kusal Mendis claimed the catch at second slip but the third-umpire clarified that the catch had been grassed. The openers stayed unbeaten and polished off the chase in 13.2 overs to help the side complete a series sweep and bag 120 World Test Champsionship points.
Brief scores: Sri Lanka 157 (Kusal Perera 60; Anrich Nortje 6-56) & 211 (Dimuth Karunaratne 103; Lungi Ngidi 4-44) lost to South Africa 302 (Dean Elgar 127; Vishwa Fernando 5-101) & 67/0 by ten wickets.