They did so in spectacular style as they inflicted the joint-heaviest defeat in tournament history on the Caribbean outfit, winning by 257 runs in Sydney.
Captain AB de Villiers was undoubtedly the star of the show as he smashed 162 not out off just 66 balls to inspire the Proteas to a mammoth total of 408-5.
Read Sports Mole's over-by-over updates below to relive how the carnage unfolded.
De Kock tries to give himself room, only to cut the ball straight to Andre Russell at point. It is a simple catch and Holder has double reason to celebrate. Both he and Taylor tucked the left-hander up and frustrated him, drawing the poor shot. The plan was a good one and they executed it to perfection.
Much-needed breakthrough for the Windies and Gayle is perhaps the unlikely source! Du Plessis tries to repeat his back-foot carve of last over and there is just a bit of extra bounce, with Ramdin taking an excellent reflex up at head height after the ball flew off the edge. Faf goes for a well-compiled 62.
Two wickets in an over for Gayle! Wasn't someone questioning his introduction into the attack a minute ago? Amla is looking to work the ball to leg and pays for playing across the line as he is trapped in front of middle and leg. A review is not even considered. A great chance for a century escapes Amla, and the Proteas lose both of their set batsmen in quick succession as Gayle celebrates with a trademark dance!
A top knock from Rossouw comes to an end as he gets a thick edge through to Ramdin trying to carve Russell through the off-side. The left-hander is only in the side due to an injury to JP Duminy, but boy he has taken his chance with a combination of excellent running and clinical hitting.
Jerome Taylor takes the spotlight away from De Villiers for just a moment as he takes a brilliant catch on the boundary to dismiss Miller! Russell kneels and bows before his teammate, and rightly so after Taylor nonchalantly held on one-handed on the stretch after running round from long-on. Incredible.
"I'm not a huge fan of setting targets but we had plans in place of reaching 300 halfway through the innings. This game is only half way and the only thing on my mind is winning. We want to go and defend this total."
Gayle tries to give himself room to free his arms, but the ball from Abbott, who takes the other new ball rather than Morne Morkel, cramps him up and cannons into leg stump. Start the car.
No feet again from Samuels and he feathers the ball through to De Kock. Both of West Indies' centurions from the game against Zimbabwe, their two most senior batsmen, are gone inside four overs.
Carter is good on the pull, but Morkel perhaps just rushes him a little here. He is a bit late on the shot, the bat face closes and De Villiers scrambles to take a decent catch at mid-wicket.
Two in two balls for the Proteas, and Tahir is immediately among the wickets! He dropped a fairly simple catch off Abbott a few overs back, but his teammates do not let him down in the same manner as Miller holds on for a cracker at long-on. Smith went big first ball, and Miller made up a lot of ground from long-on to clinging on diving upwards to his left. Nearly as good as Taylor's earlier!
It is all going horribly wrong for the Windies. Tahir traps Simmons with what looked like the googly, and umpire Steve Davis gives the lbw. Simmons trudges off for a second-ball duck without reviewing, despite there appearing to be an inside edge. That may be a case of throwing in the towel.
JP Duminy's wife (far right) and some of the other lady Proteas will certainly be enjoying what they are watching from the VIP boxes at the SCG. I'm suddenly enjoying my morning a lot more too.
Tahir has another and it's the googly again. Sammy backs away to try to hit over extra cover, with the ball spinning in between bat and pad. De Kock quickly whips the bails off and the third umpire confirms that his foot was raised and not back in time. Smart work with the gloves and Tahir goes on another lap of honour.
It is two in an over for Tahir again as Russell slices an attempted cut to short third-man, where Abbott takes a good catch diving forward. It is a tragic performance from the Windies, but South Africa deserve huge credit for remaining ruthless and focused in the field despite the contest long being over.
Tahir wheels off in celebration after securing a World Cup five-for. It is another googly which fools Ramdin and goes through his open defences. Beautiful bowling from the leggie, who now has 5-32.
Holder's valiant stand comes to an end as Steyn picks up his first wicket. His bouncer is simply too quick for Holder, whose attempted pull hits the splice of his bat and loops straight to Amla at mid-on.
No, they can't! Benn can do nothing with a rising Morkel delivery which would have been plenty good enough for more esteemed batsman, and an edge goes straight into the hands of Amla at slip.
"The main thing is to know your own game, know your strengths and weaknesses and when to hone in on the former. I enjoy myself out there. I see it is getting momentum and reading the situation in the middle. I earned the right to have a go at the bowlers in the latter stages of the innings."