Faf du Plessis fell agonisingly short of hitting a South African record one-day international score, but his 185 contributed to another milestone against Sri Lanka.
Gary Kirsten's mark of 188 remains safe for another day, with Du Plessis scoring his runs from 141 balls, striking 16 fours and three maximums.
The Proteas had already wrapped up the series 3-0 ahead of match four at Newlands, perhaps allowing for some freer hitting from the batsmen after captain AB de Villiers won the toss and elected to bat.
Du Plessis was swiftly called into action when Hashim Amla fell in the second over, but the Test skipper combined for 100 runs with Quinton de Kock before adding another 137 along with De Villiers.
Often associated with power hitting, this was a composed knock from Du Plessis, dealing mainly in singles and fours as he stormed past his previous best in the 50-over arena of 133 not out before aiming his sights closer to the 200 mark.
-- OptaJim (@OptaJim) February 7, 2017
Starting the final over on 185, Du Plessis skied his first ball down to the long-on boundary, where Asela Gunaratne was waiting to deny him a place in history.
Regardless, Du Plessis' contribution had its uses, pipping David Warner's previous best in Cape Town of 173 and helping South Africa post the highest ODI total at Newlands as they finished their allocation on 367-5.
367 - South Africa's score of 367/5 (v Sri Lanka) is the highest ever registered in an ODI innings at Newlands. Imposing.-- OptaJim (@OptaJim) February 7, 2017