South Africa 158 for 4 (de Kock 70, van der Dussen 37, Richardson 2-21) beat Australia 146 for 6 (Warner 67*, Ngidi 3-41) by 12 runs
Port Elizabeth: Spirited South Africa defeated Australia by 12 runs in the thrilling second T20I at St George's Park, Port Elizabeth on Sunday.
In the last over, Australia required 17 runs to win the match but could manage to score only four runs.
Chasing a moderate target of 159, Australia had a solid start as David Warner and skipper Aaron Finch added 48 runs for the first wicket in just 28 balls.
Finch was bowled out by pacer Lungi Ngidi in the fifth over.
Steve Smith and Warner then built a 50-run partnership for the second wicket.
Smith scored 29 runs before being caught by Faf du Plessis off Dwaine Pretorius.
Alex Carey played a knock of 14 runs and was bowled out by Ngidi, reducing the visitors to 124/3 in 15.3 overs.
In a turn of events, Australia lost three quick wickets as Mitchell Marsh (6), Matthew Wade (1), and Ashton Agar (1) were departed cheaply.
Warner remained unbeaten at 67 runs off 54 balls but could not put his side over the line.
Australia were only able to score 146/6 in their twenty overs.
Earlier, the hosts won the toss and opted to bat first.
Skipper Quinton de Kock and Reeza Hendricks built a quickfire 60-run opening stand in 39 balls.
Kane Richardson got rid of Hendricks (14) in the seventh over.
Faf du Plessis joined De Kock in the middle and built a brief partnership of 21-run for the second wicket.
Plessis was picked by pacer Pat Cummins in the 11th over after scoring 15 runs.
De Kock and Rassie van der Dussen had the second-highest partnership of the innings as they put up a stand of 40-run.
Adam Zampa provided the crucial breakthrough for his side as he dismissed danger looking De Kock in the 15th over.
De Kock played a knock of 70 runs off 47 balls studded with five fours and four sixes.
Van der Dussen after playing a knock of 37 runs was scalped by Richardson in the 19th over.
David Miller and Pite van Biljon played an unbeaten knock of 11 and seven runs respectively.
For Australia, Kane Richardson bagged two wickets and returned with the figures of 2-21 in his four overs.