Australia 277 for 9 (Mooney 82*, Healy 60, McGrath 44, Klaas 4-56) beat South Africa 127 (Luus 34, King 4-26, Garth 3-14, McGrath 3-23) by 110 runs (DLS method)
Standout performances from Beth Mooney and Tahlia McGrath enabled Australia to recover their composure after the heavy defeat three days ago to secure the ODI series in convincing style. It means they are 8-4 ahead in the multi-format contest leading into the Test match, and can't be overtaken.
Mooney anchored Australia's innings with an unbeaten 82 off 91 balls without ever finding top gear after Alyssa Healy had struck a crisp half-century. South Africa kept themselves in the game by removing McGrath and Ash Gardner in quick succession, but Annabel Sutherland and Alana King played handy innings down the order alongside Mooney.
McGrath and Kim Garth then did the significant damage with the ball. Garth's swing accounted for Laura Wolvaardt and Anneke Bosch, while McGrath had Tazmin Brits and the key wicket of Marizanne Kapp both held in the deep in the space of four balls.
Rain interrupted South Africa's chase after 14 overs and for a while looked like it may not relent to allow the game to be completed, but it resumed as a 31-over contest. South Africa immediately needed ten an over, which proved way beyond them and wickets fell in a rush including three in an over for King, who was a whisker away from a hat-trick.
South Africa had made an encouraging start after Healy won another toss. Phoebe Litchfield's lean series continued when she found cover, and after seven overs Australia had been held to 21 for 1 with Kapp producing an opening spell of 4-2-5-0.
But Healy, who was given a life on 27 when a very tough chance was spilled at deep square-leg, started to increase the tempo alongside Ellyse Perry as the pair added 82 for the second wicket. Masabata Klaas produced a brilliant inswinger to remove Perry, and after passing fifty from 61 balls, Healy somewhat carelessly flicked to deep square-leg.
Mooney, who took 13 balls to get off the mark, and McGrath built another important stand, although progress was often hard work. McGrath broke the shackles with five consecutive boundaries off Ayanda Hlubi but was beaten by one that skidded through from Chloe Tryon in the next over. Gardner was then pinned lbw by Kapp to leave Australia 187 for 5 in the 37th over.
Mooney brought up her fifty from 71 balls and would go on to add 32 from her next 20 deliveries as Australia accelerated in the final ten overs. A brace of superb catches - one by Wolvaardt at cover and another by Nadine de Klerk in her follow through - dented Australia's ambitions a little, but their total was given a boost when 13 runs effectively came from one delivery. King swung a huge full toss from Klaas for six (demolishing her stumps in the process) and then dispatched the free hit as well.
Wolvaardt has not managed to get going in the ODIs and soon edged Garth to first slip. At the other end, Darcie Brown, who replaced a rested Megan Schutt, was bowling with good pace and struck Brits a nasty blow on the wrist.
Brits fought through the pain before finding deep midwicket and South Africa's best hope then vanished when Kapp, who had been so inspirational in the second game, helped McGrath into the hands of deep-backward square-leg.
Either side of the rain delay, de Klerk and Sune Luus added 50 but Australia had plenty of breathing space.
