The hardest job on day four in Port Elizabeth was not chasing 101 for victory. Through the majesty of AB de Villiers, South Africa did that with ease and levelled the series 1-1. No, the most difficult task was assigned to whoever chose the Man of the Match. Would it be de Villiers, whose unbeaten 126 in the first innings was not only a game-changer but one of the most impressive knocks in recent history, and whose run-a-ball 28 in the second innings helped seal the win? Or would it be Kagiso Rabada, whose 11-wicket haul was irresistible to watch and completely blunted Australia's batting?

Certainly it was Rabada who lit up the morning session at St George's Park. South Africa began the day clearly in the stronger position, but Australia were 41 runs ahead and still had five wickets in hand. If they let Australia's lower order off the hook, South Africa could have been faced with a tricky chase of 200-plus. The key seemed to be Mitchell Marsh, the last member of Australia's top six, who was unbeaten on 39 at the start of play. Rabada didn't even let Marsh survive an over. He nipped one back in to Marsh, at speed, to find the gap and rattle his stumps.

Rabada followed by having Pat Cummins caught by Theunis de Bruyn at gully for 5, and he added Mitchell Starc, who was caught behind for 1. Rabada finished with match figures of 11 for 150, and he became just the third South African to achieve a ten-wicket Test haul on at least four occasions. For perspective, the others are Dale Steyn, whose five ten-wicket hauls have come in 86 Tests, and Makhaya Ntini, whose 101-Test career brought four ten-fors. Rabada has four in just his 28th Test. He is still only 22 years old. This is a young man who could be absolutely anything.

Perhaps a caveat is needed to the earlier statement. There was one other task on day four that might have been even harder than determining the Man of the Match. This job fell to match referee Jeff Crowe, who had to decide whether Rabada would be suspended for the remainder of the series for his shoulder bump with Steven Smith during Australia's first innings. In isolation, the incident would not be worthy of a ban, but Rabada's bank of demerit points changes that. After a hearing on day three, Crowe chose to defer his verdict for 24 hours.

Australia's innings finished with Nathan Lyon being caught behind off Lungi Ngidi for 5 and Josh Hazlewood caught at deep midwicket off Keshav Maharaj for 17. Tim Paine remained unbeaten on 28 in Australia's 239, and their lead of 100 was never likely to be truly competitive. One of the major concerns for Australia as they head to the third Test in Cape Town is that not a single Australian batsman has scored a century so far in this series. South Africa, by comparison, have had hundreds in each Test - from Aiden Markram in Durban and de Villiers in Port Elizabeth.

Australia had the chance to snap up Markram for 7 in this chase, but his edge off Hazlewood was put down at first slip by Mitchell Marsh, hardly a promising start for a team needing a miracle to avoid defeat. Wickets did fall, but not enough. Dean Elgar was caught and bowled by Lyon off a leading edge for 5, in a near carbon-copy of his dismissal in the first innings in Durban, and Markram was caught at second slip by Smith off Hazlewood for 21, but all that did was bring de Villiers to the crease.

Australia's minor sniff was snuffed out by the aggression of de Villiers, who struck four fours and one six during his 28 off 26 balls, and his 49-run stand with Hashim Amla delivered South Africa to within 20 runs of victory. Both men fell - Amla caught behind off Cummins for 27 and de Villiers caught at short-leg off Lyon - but Faf du Plessis and de Bruyn steered South Africa home with no further loss, a cover-driven boundary from de Bruyn confirming the six-wicket win.

The teams will head to Cape Town for the third Test with South Africa looking in the stronger form, but potentially without their strike bowler Rabada, who is far and away on top of the series wicket tally with 15 at 16.80. Whether they are the same threat without him remains to be seen. And, just for the record, in the race to be Man of the Match, Rabada beat de Villiers by a nose.