Left-arm spinner Ashton Agar became just the second Australian to take a T20I hat-trick, as well as the second Australian to take a five-for in the format, as the visitors dominated South Africa in a 107-run victory.
Australia, having been put in to bat, could have been in trouble as they lost David Warner to just the second ball of the innings for 4; Dale Steyn extracting some steepling bounce from the surface to take the top edge of the opener's attempted pull shot.
But the home side's bowlers proceded to bowl too short to Steve Smith and Aaron Finch and were punished for it as the pair built an 80-run partnership in 48 balls. Finch's dismissal for 42 did a little to slow the run rate, before Matthew Wade and Steve Smith were both sent on their way in the space of three balls, for 18 and 45 respectively. Smith in particular will have been frustrated with his dismissal, stumped off a leg-side wide from Tabraiz Shamsi, who appeared to spot Smith's intentions to charge down the wicket early.
The innings threatened to stall with two new batsmen at the crease, but Mitchell Marsh and Alex Carey both did just enough to keep the momentum going, plundering 16 runs from an over by Kagiso Rabada in the middle of an otherwise quiet period in which JJ Smuts, Andile Phehlukwayo and Dale Steyn conceded a combined 18 runs from three overs.
Ashton Agar made his first impact on the game with the bat, taking up the mantel to keep the innings going as he drilled a trio of boundaries in the final over, picking up 18 runs from it and setting a competitive total of 196/6.
It quickly transpired to be more than competitive as South Africa lost their own destructive opening batsman, captain Quinton de Kock, bowled by a peach of a delivery from Mitchell Starc in the opening over of the chase.
That set the tone as South African wickets tumbled. Cummins picked up the pair of Rassie van der Dussen and JJ Smuts in consecutive overs before David Miller fell victim to Adam Zampa's leg-spin.
Four wickets down after seven overs, the worst was yet to come for the hosts, as Ashton Agar prcoeded to remove former captain Faf du Plessis, the only batsman who had shown resistance up to now, for 24, caught on the cover boundary. Next ball Andile Phehlukwayo was struck on the pads and sent on his way for a golden duck, and Dale Steyn quickly followed for a first-baller of his own, edging an expansive drive to slip.
He nearly made history after taking another two wickets with consecutive deliveries. It was only the smallest of margins which denied him becoming the first bowler to record two hat-tricks in the same T20I, as the ball just passed Tabraiz Shamsi's off-stump without disturbing it. Nevertheless he finished with figures of 5/22, his maiden T20I five-wicket haul, and was the chief destroyer.
Adam Zampa picked up the final wicket to leave South Africa all out for 89, their lowest score in T20Is falling nine runs short of the 98 they made against Sri Lanka in 2018.
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