The result re-ignited South Africa's hopes of reaching the semi-finals, and the buoyant mood in the camp was a far cry from Guyana on Saturday when Bangladesh clinched a shock win over Graeme Smith's team.
The South Africans came into the tournament as the top ranked side, a distinction that has since been reclaimed by Australia, and losing to Bangladesh gave them pause for thought.
"We felt we were a little bit tentative against Bangladesh, and we wanted to come out and express ourselves and not restrict ourselves in the way we play," Smith said after Tuesday's match.
"We got ourselves to the top ranking by playing a certain style of cricket, and we discussed how during that Bangladesh game we put ourselves under pressure by not sticking to what we naturally know how to do and what's worked for us.
"We wanted to go back to that today (Tuesday) and allow ourselves to play with that freedom."
Freedom to play booming strokes was part of opener AB de Villiers's approach on Tuesday, when he scored 146, his maiden one-day international century, to boost South Africa to a total of 356 for four, their record World Cup score. In reply, the West Indies laboured to 289 for nine.
South Africa will need more of the same from their players on Saturday, when they take on a New Zealand team that has racked up nine consecutive wins in one-day internationals.
Smith expected a tense, competitive match against the Black Caps, who are on top of the standings after reeling off a string of convincing wins.
"New Zealand have played well in the tournament, and they're a pretty balanced team," Smith said. "They bat pretty low and they have a lot of options in their bowling department.
"We have performed well at times against New Zealand and they have beaten us at times.
"If we can play the type of game we played on Tuesday, with our natural ability and allowing ourselves the freedom to play that way, setting up opportunities to attack, it will bode well."
South Africa whitewashed New Zealand In a home series last season, but the New Zealanders could have the edge in conditions that should suit them better.