Quinton de Kock hit his fourth century of the World Cup while Rassie van der Dussen cracked his second as South Africa thrashed New Zealand by 190 runs on Wednesday to take a step closer to the semi-finals.

The Proteas' commanding 357-4 was built on De Kock's 114 and Van der Dussen's 133.

New Zealand, just days from only narrowly falling short chasing 389 in a five-run defeat by Australia, collapsed to 190 all out with more than 14 overs left in Pune.

Marco Jansen (3-31) and his fellow South Africa fast bowlers ripped through the top order -- still without the injured Kane Williamson -- as New Zealand slumped to 67-4.

Left-arm spinner Keshav Maharaj (4-46) then strengthened South Africa's grip on the game as the Black Caps collapsed to 110-8.

Glenn Phillips made a defiant 60 but the game had long been over as a contest by the time he was last man out.

Victory, which ended South Africa's run of five straight World Cup defeats by New Zealand since 1999, left the Proteas, bidding for a first one-day international World Cup title, virtually assured of a semi-final spot.

"Quinny played brilliantly," said Van der Dussen afterwards.

"They (New Zealand) did well to keep a lid on us for large part of the innings, but we knew if Quinny and I could take it deep we could get momentum on our side."

New Zealand's third loss of the tournament was a blow to their hopes of reaching the last four as they slipped to fourth in the table with eight points, two ahead of Pakistan as well as Afghanistan who have a game in hand.

"It's important we reflect on this one quickly and go into the next game with a positive mind, you don't become a bad team overnight," said New Zealand captain Tom Latham.

By opting to field upon winning the toss, Latham played into South Africa's strength.

He defended his call by saying: "You expect yourself to perform at your best, but those two (De Kock and Van der Dussen) played fantastically well."

Left-handed opener De Kock reached his 21st ODI ton off 103 balls with eight fours and three sixes.

He brought up his century with a huge six off Jimmy Neesham.

"I'm feeling really good lately. It's nice that everything is coming together at an important time for us," said De Kock, who plans to quit ODI cricket after this tournament, at the innings break.

He added: "My career is coming down to a finish, I'm trying to bat as much as I can."

De Kock also made 100 against Sri Lanka, 109 in the game with Australia and 174 in the victory over Bangladesh.

He started the day needing just 69 more runs to pass 500 for the tournament and broke through that barrier with a legside boundary off recalled paceman Tim Southee.

He was eventually out for 114 caught by Phillips off Southee, ending a 200-run partnership for the second wicket.

Van der Dussen maintained the assault with 133 off 118 balls, including nine fours and five sixes.

It was his second hundred of the tournament after his 108 against Sri Lanka and sixth of his ODI career.

Southee clean bowled Van der Dussen in the 48th over.

David Miller added a blistering 53 off just 30 balls with four sixes, while Aiden Markram arrivied at the wicket for the last ball which he smashed for six.

New Zealand used seven bowlers after seamer Matt Henry suffered a hamstring injury and left the field midway through his sixth over.

(AFP)