AUCKLAND: South Africa-born Grant Elliott's brilliant 84 not out, capped with a stunning six off the penultimate ball, saw New Zealand to a four-wicket win over the Proteas in a cliffhanger World Cup semi-final at Auckland's Eden Park on Tuesday.

Elliott's winning six, off injured South Africa fast bowler Dale Steyn, took New Zealand into the World Cup final for the first time and they will play the winner of Thursday's second semi, between Australia and India in Sydney, in Sunday's showpiece match in Melbourne.

New Zealand v South Africa - As it happened

New Zealand faced a revised target of 298 under the Duckworth/Lewis method after South Africa made 281 for five in 43 overs, which included a near two-hour rain stoppage.

Black Caps skipper Brendon McCullum made a typically quickfire 59 off 26 balls at the head of the innings. Then came a valuable 103-run partnership between Elliott and Corey Anderson and New Zealand appeared to have the game in hand with six overs to go.

But Morne Morkel regained the initiative for South Africa by taking a wicket and conceding only one run in the 38th over and by the start of the 43rd, and final, over New Zealand required 12 to win.

They started with a bye, a single, a four to Daniel Vettori, another bye and then Johannesburg-born Elliott, who turned 36 last weekend, smacked Steyn high into the stands as New Zealand, after losing all six of their previous World Cup semi-finals, completed a thrilling win.

South Africa, struggling to throw off their unwanted “choker” tag, have now failed to win all four World Cup semi-finals they have contested.

As McCullum flung his bat at the start of New Zealand's run chase, South Africa captain AB de Villiers was forced to take three of his frontline bowlers out of the attack.

Vernon Philander, replacing Kyle Abbott in the side, gave up 14 runs to McCullum with his first over and was immediately replaced by Morkel.

Morkel also lasted one over that cost 14 runs but came back from the other end after Steyn was spelled when McCullum hit two sixes and three fours off his third over.

Steyn is consoled by teammate JP Duminy after South Africa's loss. — Reuters

The return of fast bowler Morkel paid immediate dividends. He undid McCullum who plopped a simple catch into the hands of Steyn at mid-on and in his next over he bowled Kane Williamson.

After nine overs, New Zealand were 81 for two.

Martin Guptill, looking to back up his World Cup record 237 not out against the West Indies in last weekend's quarter-final, looked in fine touch making 34 before being run out in a mid-pitch mix-up with Ross Taylor.

Taylor did not last much longer before he was caught behind and New Zealand were 149 for four when Elliott and Anderson set up camp before the latter was out for 58..

De Villiers had set South Africa up for a big finish with heavy hitters in hand only to be denied seven overs when rain swept in when they were 216 for three in the 38th over.

He produced a rapid 65 not out and, following the rain break, David Miller's boundary-laden 49 from 18 deliveries got South Africa up to 281 for five

De Villiers was in command in the lead up to the near two-hour rain disruption cracking 60 off 38 balls, but when the weather cleared and play resumed he could only stand and watch as Miller took charge.

Of the 65 put on in the five overs after the resumption, Miller scored 49 after replacing Faf du Plessis who was out for 82 on the second ball after the restart,

Luck was with South Africa when they won the toss, elected to bat and gained early momentum when edges raced to the short boundaries.

New Zealand wicket-keeper Luke Ronchi dropped Quinton de Kock on six and Trent Boult missed a difficult chance to catch Hashim Amla.

But left-arm paceman Boult, the tournament's leading bowler with 21 wickets, added to his tally by dismissing Amla and de Kock on his way to figures of two for 53.

Elliott dedicates win to long-suffering fans

Elliott dedicated New Zealand's thrilling four-wicket win to long-suffering Kiwi fans after his undefeated 84 steered the Black Caps into a first World Cup final after six previous semi-final losses.

Elliott, who turned 36 at the weekend, hit a six off the penultimate ball to take New Zealand into Sunday's final in Melbourne where they will face either Australia or defending champions India.

“It is great. I don't think this win is for myself, or the team, it is for everyone here. The support has been amazing,” said Elliott, who smashed Dale Steyn into the stands for the match-clinching six.

New Zealand players thank their fans after their victory. — AFP

“We just wanted to take it as deep as we could. Corey Anderson (58) batted well and we timed the innings to perfection.

“When you have 40,000 fans screaming at you every ball, it has been an absolute pleasure playing at Eden Park and playing in front of the home crowd.”

“We have had a good run, this is the first final we have been in and we will approach it as any other match.”

Skipper Brendon McCullum made a 26-ball 59 to also help the Black Caps to their rain-adjusted target of 298 after South Africa had made 281 for five batting first in a match reduced to 43 overs per side.

For South Africa, Faf du Plessis made 82, captain AB de Villiers was not out 65, while David Miller smashed an 18-ball 49.

But the rain came at the worst possible time as they were well-set at 216 for three in the 38th over when play was halted for two hours.

“These boys, I am so proud of them. A lesser team would have laid down today. To see Grant come in and be as calm as he was... we've given ourselves a chance of the big prize,” said McCullum.

“Credit to South Africa, they gave as good as they got. I feel for them at the moment. But our boys were outstanding. And it was a great semi-final.”

De Villiers was distraught as South Africa, who've yet to reach a World Cup final, once again came up short.

“It's really painful but we have no regrets. We left it all out on the field. We had opportunities and it will take us a long time to get over this,” he said.

“All the best to New Zealand -- they played a great game.”