Australia 125 for 4 (McGrath 57, Kapp 2-21) beat South Africa 124 for 6 (Brits 45, Wareham 2-18) by six wickets
It was Australia's fourth successive win in the competition and their sixth victory against South Africa in as many matches at T20 World Cups. South Africa have now endured their second defeat in three matches and sit third in Group 1 behind Sri Lanka. They will have to win their next game against Bangladesh and hope Sri Lanka lose to New Zealand on Sunday to qualify for the semi-finals.
Brits made good use of the field setting in the powerplay and used her feet well to come down the track and hit boundaries to keep ticking. After Ellyse Perry removed Wolvaardt in the ninth over for a 28-ball 19, she punished Annabel Sutherland in the next over for a six and four to ensure South Africa didn't slow down. Brits eventually was out five short a half-century - her best score of the tournament - hitting six fours and a six.
Wareham, pacers pull things back
Australia fought back after the ten-over mark with regular wickets to keep South Africa at bay. After scoring 65 runs in the first ten for the loss of one wicket, South Africa could muster only 59 in the final ten, losing the plot as well as five wickets.
Ashleigh Gardner picked up her 50th T20I wicket when she bowled Luus out in the final over. Darcie Brown, and Megan Schutt also accounted for a wicket each for Australia.
Kapp, Mlaba strike early blows
Left-arm spinner Nonkululeko Mlaba, who opened with the ball, then bowled Meg Lanning the next over when she tried to scoop a length ball over fine leg and missed badly. Kapp came back in the next over to trap Beth Mooney lbw with a full inswinger. At the end of the seventh over, Australia's top order was back in the pavilion for 40 runs.
McGrath blitz takes Australia home
Gardner and McGrath then put on a match-winning 81-run partnership for the fourth wicket to blunt South Africa's attack. McGrath was the more proactive among the two, counterattacking from the word go. She started with two fours against Nadine de Klerk in the 10th over to eventually race to a 29-ball half-century, which was also McGrath's first fifty in this T20 World Cup.