15th September 2023
Klaasen was brutal on the Australia bowling attack as he smashed 174 off just 83 balls as the hosts amassed a total of 416-5 before the visitors replied with 252 all out.
Having notched scores of 14, 40 and 0 in the series heading into Friday's contest, Klaasen wanted to hit some sort of form ahead of the World Cup that starts early next month.
And the middle-order batter certainly made his presence felt at his home ground as he struck 13 fours and powered as many sixes against a stunned bowling attack.
Klaasen made his way to the crease in the 26th over with the total on 120-3 and brought up his first fifty off 38 balls.
Klaasen and David Miller (82 not out off 45 balls) shared in a fifth-wicket stand of 222, a record at the venue and against Australia as the pair went on a rampage.
The Proteas initially had a sedate start to the innings compared to the end with Quinton de Kock (45) and Reeza Hendricks (28) putting on 64 in 13 overs.
Stand-in captain Aiden Markram (8) fell cheaply before Rassie van der Dussen (62 off 65) and Klaasen added 74 off 57 deliveries before the Klaasen and Miller show.
Seamer Josh Hazlewood and spinner Adam Zampa finished with their most expensive figures in ODIs - 2-79 and 0-113 respectively - with Zampa's also the joint-most expensive by an Australian in ODIs.
Australia knew they needed a quick start with the bat in the run-chase but they lost two early wickets as Lungi Ngidi removed both David Warner and captain Mitch Marsh to leave the visitors on 22-2.
Opener Travis Head was forced to leave the field and never returned after a blow to his hand from a fast delivery from paceman Gerald Coetzee.
Tim David tried in vein to keep up with the required scoring rate as he made his way to 35 from 25 balls but the hosts kept taking wickets at regular intervals.
Alex Carey led a lone fight and was unlucky to be last man out for 99 off just 77 balls for Australia as Lungi Ngidi finished with figures of 4-51 in eight overs.
The Proteas will also be happy with paceman Kagiso Rabada as he took three wickets, including Carey, and conceded 41 runs in 7.5 overs.
The fifth and deciding ODI of the series will take place at the Wanderers on Sunday.