With the pro-Bangladeshi crowd whipped up by their team suddenly back in contention, any hint of a dismissal was wildly cheered. Santner and Henry got off the mark with singles and combined for 20 runs in less than three overs. Then Henry was bowled for 6 with New Zealand needing seven to win and two wickets left.
Santner and Lockie Ferguson held their nerve, and the end came in a rush thanks to two wides, a Ferguson tickle to the third man boundary, and a Santner boundary through the covers to complete the victory with 17 balls to spare.
Bangladeshis packed the Oval in hope of a double celebration beside Eid al-Fitr, the holiday marking the end of Ramadan, but they had little to cheer in the first half of the match. Bangladesh was bowled out for 244 inside 50 overs, put in on a fresh pitch which was slower than expected.
The top five batsmen all made starts but invariably got themselves out under pressure to escape New Zealand's grip. Shakib Al Hasan, the third Bangladeshi to play 200 ODIs, top scored with 64. He was the only batsman to make more than 30.
The New Zealand battery, backed up by smart fielding, was disciplined and Henry led with 4-47.
Halfway through its innings, New Zealand was cruising in its chase of 245 at 138-2 against Bangladesh, after a dramatic start at the Oval.
Shakib Al Hasan removed openers Martin Guptill (25) and Colin Munro (24), and should have had captain Kane Williamson run out on 8 while he was bowling.
Williamson was short of the crease by more than a foot when the bails were taken out, but video showed wicketkeeper Mushfiqur Rahim knocked off the bails with his right arm before he caught the ball.
Then Ross Taylor, while on 10, survived being run out by an inch. He was fortunate the throw to Mushfiqur was too high.
Taylor and Williamson got their communication sorted out, settled down, and used their reprieves to reach their 26th partnership of 50-plus in ODIs.
After 25 overs, Taylor, the aggressor, was on 53 and Williamson on 35.
An opening victory for India has South Africa's Cricket World Cup campaign teetering on the edge.
Rohit Sharma made the most of an early reprieve to post an unbeaten 122 and guide India to a six-wicket win over an injury-depleted South Africa.
Sharma's let off came in the second over — Kagiso Rabada's first — when he fended at a short ball which brushed his glove and carried to second slip, but South Africa skipper Faf du Plessis wasn't able to grab it.
He was also dropped on 107 before India surpassed the victory target of 228 with 15 balls to spare, consigning South Africa to a third straight defeat.
After waiting until day seven to get its campaign started, India will have to turn around quickly to play defending champion Australia at the Oval on Sunday. South Africa remains in Southampton to face West Indies, needing a convincing win to maintain any hope of advancing to the playoffs.
Bangladesh was all out for 244 after New Zealand won the toss and put the squeeze on at the Oval in their day-night match.
The top five batsmen all made starts but invariably got themselves out under pressure to escape New Zealand's grip.
Shakib Al Hasan, the third Bangladeshi to play 200 ODIs, top scored with 64. He was the only batsman to score more than 30.
The New Zealand battery, backed up by smart fielding, took advantage of a fresh pitch, overcast skies, and disciplined bowling to set a gettable target.
Matt Henry returned 4-47 and Trent Boult snared a pair of wickets, while Lockie Ferguson, Colin de Grandhomme, and Mitchell Santner took one each.
Santner, the slow left-armer, was unhittable through the middle overs, not conceding a boundary until his ninth over, and the only six of the match in his 10th. But his performance will also have heartened the Bangladesh spinners.
New Zealand has a 4-0 win record against Bangladesh at the World Cup, batting second each time.
India is 95-2 after 25 overs, chasing 228 for victory in its opening Cricket World Cup against South Africa.
Rohit Sharma is unbeaten on 53 after surviving a dropped catch in the second over, and KL Rahul is 13.
Kagiso Rabada bowled with pace and aggression early and had Shikhar Dhawan (8) caught behind to get South Africa off to a promising start defending a small total at the Rose Bowl. He then met India skipper Virat Kohli with a bumper and had 1-3 after three overs, before Sharma went on the attack by hitting a six and two boundaries in Rabada's next over.
Kohli was out for 18 to an athletic, tumbling caught behind by Quinton de Kock off Andile Phehlukwayo as India stumbled at 54-2.
Sharma's 50, the first off the match, came off 70 balls.
West Indies expects opener Chris Gayle and allrounder Andre Russell to be fit to play against Australia on Thursday.
Both players came off the field in apparent pain during the Windies' seven-wicket win over Pakistan last week, with Gayle's longstanding back complaint flaring up and Russell aggravating a left knee problem when fielding.
West Indies captain Jason Holder says Gayle has been practicing with the team the past two days so is "well and ready to go." He adds Russell will be assessed before the game against Australia but that selectors are "very, very hopeful that he will be fit."
Yuzvendra Chahal snared four wickets after Jasprit Bumrah removed both openers in a torrid opening spell as India opened its Cricket World Cup campaign by restricting South Africa to 227-9 at the Rose Bowl.
Injury-depleted South Africa's campaign went from bad to worse on Wednesday after electing to bat and coming under immediate fire.
Bumrah (2-35) took the first two wickets, generating good pace and significant seam movement, and wrist spinner Chahal (4-51) started with a pair in one over including the key wicket of Faf du Plessis.
South Africa is coming off losses to England and Bangladesh and its World Cup campaign is unraveling as injuries to fast bowlers diminishes its pace attack.
The India squad had to wait until day seven of the tournament to get started, and Bumrah didn't waste time getting things going when he had Hashim Amla (6) caught edging to second slip in the fourth over and Quinton de Kock (10) caught at third slip by Virat Kohli in the sixth.
Du Plessis (38) and Rassie van der Dussen (22) survived the new ball and combined in a 54-run third-wicket revival before Chahal started and finished the 20th over with their wickets as South Africa slipped to 80-4.
Chris Morris (42) and Kagiso Rabada (31 not out) put on 66 runs off 62 balls for the eighth wicket to carry South Africa to the 50th over.
New Zealand has won the toss and will bowl first against Bangladesh in their day-night match at the Oval.
New Zealand is unchanged from the side which beat Sri Lanka by 10 wickets on Saturday.
Bangladesh is also unchanged after beating South Africa by 21 runs at the Oval on Sunday. Allrounder Shakib Al Hasan will become the third Bangladeshi to play 200 one-day internationals.
New Zealand has a 4-0 record against Bangladesh in the Cricket World Cup.
It's cloudy but expected to remain dry at the Oval.
Bangladesh: Tamim Iqbal, Soumya Sarkar, Shakib Al Hasan, Mushfiqur Rahim, Mohammad Mithun, Mahmudullah, Mosaddek Hossain, Mohammad Saifuddin, Mehedi Hasan, Mashrafe Mortaza (captain), Mustafizur Rahman.
New Zealand: Martin Guptill, Colin Munro, Kane Williamson (captain), Ross Taylor, Tom Latham, Jimmy Neesham, Colin de Grandhomme, Mitchell Santner, Matt Henry, Lockie Ferguson, Trent Boult.
Australia captain Aaron Finch supports the introduction of concussion substitutes in international cricket — provided everyone "plays ball" with the rules.
A report in British newspaper The Daily Telegraph said mid-match substitutions for players ruled out for being concussed could be permitted from Oct. 1. A two-year trial began in domestic cricket in countries including Australia, England and India from October 2017.
Finch says "you don't want the game to be determined by someone getting hit and being out of the game. If that happens in the first over, it's a huge disadvantage."
In trials, teams have only been allowed to make like-for-like replacements for a concussed player. That prevents manipulation of the rule, for example a batsman being replaced by a bowler just before a team ends its innings and goes out to bowl.
Finch says "if everyone plays ball, I think it's a good decision" because "a game of cricket isn't as important as someone's health."
South Africa is in serious trouble after slumping to 103-5 halfway through its allotted overs in the Cricket World Cup group game against India.
Paceman Jasprit Bumrah removed openers Hashim Amla (6) and Quinton de Kock (10) in a torrid, five-over opening spell that netted him 2-13 and, after a 54-run third-wicket revival by the South Africans, wrist spinner Yuzvendra Chahal started and finished the 20th over with wickets.
Rassie van der Dussen (22) was bowled attempting a reverse sweep but playing all around the ball, and skipper Faf du Plessis (38) was bowled between bat and pad on the last ball of the over.
South Africa lost three wickets for 11 run and slumped to 89-5 when JP Duminy (3) was trapped lbw by left-arm wrist spinner Kuldeep Yadav.
The South Africans are coming off losses to England and Bangladesh and are struggling with injuries which forced two changes to the starting XI.
Jasprit Bumrah's lively opening spell in the World Cup has netted two wickets for India and restricted South Africa to 34-2 in the first 10 overs, the worst opening power play for a batting team in the tournament to date.
The Indian paceman extracted some prodigious seam movement to collect two key wickets. He had veteran opener Hashim Amla (6) caught at second slip in the fourth over and Quinton de Kock (10) caught at third slip by India captain Virat Kohli in the sixth to have South Africa reeling at 24-2.
Bumrah's opening five-over spell returned 2-13.
South Africa captain Faf du Plessis has won the toss and elected to bat against India in the Cricket World Cup group game at Hampshire's Rose Bowl.
It is two-time champion India's first game of the tournament following an extended break after the Indian Premier League, while South Africa is coming off losses to England and Bangladesh.
The hamstring injury to paceman Lungi Ngidi and the tournament-ending shoulder injury to Dale Steyn forced two changes for South Africa.
Left-arm wrist spinner Tabraiz Shamsi gets his first start of the tournament, and veteran opener Hashim Amla returns after missing a game because of concussion protocol and takes Aiden Markram's place at the top of the order.
India: Rohit Sharma, Shikhar Dhawan, Virat Kohli, KL Rahul, Kedar Jadhav, MS Dhoni, Hardik Pandya, Bhuvneshwar Kumar, Kuldeep Yadav, Yuzvendra Chahal, Jasprit Bumrah.
South Africa: Hashim Amla, Quinton de Kock, Faf du Plessis (captain), Rassie van der Dussen, David Miller, JP Duminy, Andile Phehlukwayo, Chris Morris, Kagiso Rabada, Imran Tahir, Tabraiz Shamsi.
It's Day 7 at the Cricket World Cup and finally Virat Kohli's India team will get its campaign under way against South Africa.
The two-time champions will be heavy favorites against a South Africa squad that is coming off losses to England and Bangladesh and has been hit by injuries.
Injured South African paceman Dale Steyn was ruled out of the tournament on the eve of the match, but opening batsman Hashim Amla is likely to be fit to play at Hampshire's Rose Bowl after missing the loss against Bangladesh because of concussion protocol.
New Zealand and Bangladesh are set to meet in a day-night match at the Oval. Both teams are coming off impressive wins. New Zealand opened with a 10-wicket thumping of Sri Lanka in Cardiff and Bangladesh beat South Africa.
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