The visitors chose to bat after winning the toss, but never dealt with the feared Proteas attack, losing wickets regularly to stumble to 122 all out. The total could've been under 100, but a last wicket stand of 26 between skipper Jason Holder and Suleiman Benn spared that embarrassment.
Leg-Spinner, Imran Tahir, again showed why he is such a factor with the ball in ODI's, claiming career best figures of 4 for 28 as the Windies managed to bat just 33.4 of their allotted 50 overs.
Tahir was ably assisted by Vernon Philander who grabbed three which included both openers, reducing the visitors to 52 for 5 at one stage.
Test Captain, Hashim Amla, and T20 Captain, Faf du Plessis, then combined for an unbeaten 97-run second wicket stand which saw the Proteas home to claim an unassailable 3-0 series lead.
Philander was named Momentum Man of the Match.