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New Zealand crush South Africa to reach T20 World Cup final.

Men's T20 World Cup semi-final, Kolkata

South Africa 169-8 (20 overs): Jansen 55* (30); Ravindra 2-29

New Zealand 173-1 (12.5 overs): Allen 100* (33); Seifert 58 (33)

New Zealand won by nine wickets with 43 balls remaining.

Finn Allen struck the fastest century in T20 World Cup history as a staggering performance by New Zealand demolished 2024 runners-up South Africa by nine wickets and booked the Black Caps a place in Sunday's final.

Chasing 170 after a 27-ball half-century from Marco Jansen had rescued South Africa from 77-5, Allen bludgeoned 100 not out from 33 balls, including 10 fours and eight sixes, as a ruthless New Zealand romped to victory with 43 balls to spare.

Allen bettered Chris Gayle's 47-ball century against England in 2016 by 14 deliveries, with his knock also the joint third-fastest century in men's T20 internationals.

Tim Seifert thrashed a brisk half-century of his own (58 off 33) as New Zealand's openers put on 117 runs (55 balls) for the first wicket before Allen kicked into overdrive.

He smacked 42 runs off just 11 deliveries to dominate his 56-run stand with Rachin Ravindra, including dispatching Jansen for five consecutive boundaries to complete an emphatic win.

"I am sure my parents were up watching the whole game. Hopefully they are proud," Allen said. "It was an extremely impressive start from our bowlers. They set the game up for sure. "I just looked to play a support role to Tim and if it was in my area I tried to hit it for four or six. "He has shown the world what he can do and that made it easy for me to sit back and have the best seat in the house. It was good fun batting together."

South Africa were previously unbeaten at this tournament, including a seven-wicket victory over the Black Caps in the initial group phase, but faltered with the bat after losing the toss. They lost Quinton de Kock (10) and Ryan Rickelton (0) to consecutive deliveries in the second over to slump to 12-2 while Aiden Markram (18 off 20) and David Miller (6) both failed to capitalise on being dropped on three.

When Dewald Brevis (34 off 27) chipped a routine catch to Mitchell Santner in the covers in the 11th over, it felt like game over for South Africa but Jansen found a stable partner in Tristan Stubbs (29 off 24) before bursting into life in the final five overs to propel the Proteas from 108-5 to 169-8.

Jansen put on 73 runs (48 balls) for the sixth wicket with Stubbs and struck five sixes in his unbeaten 55 off 30 balls.

However, it quickly proved nowhere near enough, with New Zealand never looking back after their destructive openers took the opening six overs for 84 runs - a powerplay score bettered only once in this tournament, by India against Namibia.

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New Zealand's Allen smashes incredible 33-ball century.

Allen is no stranger to monster scores, with this latest knock his sixth T20 century and third in a New Zealand shirt. But after posting an unbeaten 84 (50) against Nepal in the Black Caps' opener, he'd had a relatively quiet tournament.

While he registered a strike-rate above 170 in three of his next four innings, his contributions were all too brief, with 31 his highest score.

Not so against South Africa, with the 26-year-old producing a knock his captain Mitchell Santner jokingly described as "not bad" and Matt Henry hailed as "incredible".

He was initially starved of the strike, with Seifert facing 21 of the opening 30 deliveries, but when presented with an opportunity, Allen pounced, playing South Africa on the front foot and flaying boundaries for fun in a chanceless knock.

He struck two sixes in his first nine deliveries before taking the game away from South Africa in the final over of the powerplay.

Lining up Corbin Bosch, Allen dispatched the seamer for a six over backward point and four consecutive fours - one pulled, one driven down the ground, and two swiped over third - to race to 43 (15) and leave New Zealand needing just 86 runs off the remaining 14 overs.

This map of Allen's runs shows how he was particularly productive through the leg side and with ramp shots over the keeper's head. He brought up his half-century off just 19 deliveries, proving himself equally adept at hitting boundaries against spin with a four and a six off Keshav Maharaj either side of raising his bat, and required only 14 more deliveries to amass his second fifty.

Allen tucked into Bosch again on the right-armer's return to the attack in the 11th over, picking off a four and a six, before finishing the match with seven boundaries in eight balls, two against Maharaj and the remainder consecutive blows to Jansen, who finished 0-53 from his 2.5 overs.

"Finn Allen is a nightmare for a captain," said South Africa Test skipper Temba Bavuma. "He only faced about four dot balls. Every other ball he was scoring. In areas where there were gaps, he was able to find them. "It was Allen's day today. He chose the right day to play a knock like he did. That is exactly what you want - your big players to come through when the team needs you."

Finn Allen was fairly becalmed on the back foot (red bars) but once he moved on to the front foot, he dominated the South Africa bowling (green bars). This graphic shows the point of interception with the ball - Allen striking 45 runs off just 13 balls when the ball reached him between 1.5m and 2m from the stumps.

Going into this match, South Africa were the favourites not only to beat New Zealand but also to end their wait for a maiden T20 World Cup title. The unbeaten Proteas had topped Group D, the so-called group of death, before brushing aside India and West Indies in the Super 8s to book their spot in the knockout stages with a match to spare.

The tag of favourites was something they were more than happy to wear, head coach Shukri Conrad said on Wednesday, but over the course of 32.5 chastening overs, the memories of Sydney in 1992, Kolkata in 1999, Melbourne in 2015 and Barbados in 2024 came flooding back.

Their top order, which included the third-highest run-scorer in the competition in Markram, faltered for the second consecutive match, undone by spin as had happened against Zimbabwe.

It was Sikandar Raza who accounted for their openers in the powerplay on Sunday. In Kolkata, Cole McConchie struck with back-to-back deliveries in the second over as De Kock and Rickelton gifted routine catches to Lockie Ferguson and Allen, respectively, while Ravindra accounted for Markram and Miller: South Africa 77-4.

With the ball, tasked with defending a below-par 169, their bowlers were torn apart, none more so than the usually reliable Jansen, who leaked 29 runs from his two powerplay overs. Of the 12.5 overs New Zealand needed to complete their rapid chase, only three cost fewer than 10 runs.

"To get to 170 was a great effort and we felt we had a sniff. But as it goes in T20 cricket, the powerplay got off to a flyer and it was hard to pull back," said Markram. "You give credit to their openers to kill the game like they did. A bad night for us tonight. "We have to get back on the horse and prepare for the future. It feels like a slap in the face and we need to be better as a team."

South Africa have now lost three of their four men's T20 World Cup semi-finals and four out of five knockout matches. In the 50-over tournament, all five of their semi-final outings have ended in defeat. They might have broken their duck with victory in the World Test Championship final last June, but their reputation as chokers remains.

Allen's 33-ball century steamrollers South Africa - as it happened.

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