Kane Williamson marked his return to the World Cup with an undefeated 78 as New Zealand cruised past Bangladesh by eight wickets on Friday but the captain was forced to retire hurt with a thumb injury.
Williamson had been sidelined with a serious knee injury picked up during the IPL and sat out New Zealand's first two wins at the World Cup.
Chasing 246 to win, the 33-year-old, playing his first ODI since January, had reached his 43rd fifty in the format off 81 balls and was looking well set for a century.
He moved on to 78 with eight fours and a six when he had to call it quits after a throw from the deep rapped him painfully on the glove, jamming his thumb against the bat handle.
In discussion with the medical team, and with the Black Caps only 46 runs short of victory, it was decided to take Williamson out of the game.
"Not sure just yet," said Williamson when asked about the gravity of the injury. "It got a bit fat and colourful straight away which made holding the bat difficult. I'll have a scan tomorrow and hopefully it's okay."
New Zealand comfortably wrapped up their third win with 43 balls to spare. Williamson had put on a second-wicket stand of 80 with opener Devon Conway (45) and then 108 with Daryl Mitchell who raced to his 50 off 43 balls.
Mitchell did it in some style with a giant heave for six off Bangladesh seamer Shoriful Islam. Mitchell finished undefeated on 89 off just 67 deliveries, with six fours and four sixes under his belt.
New Zealand, runners-up at the 2015 and 2019 World Cups, had already defeated defending champions England as well as outsiders Netherlands in India. Bangladesh defeated Afghanistan and then lost to England.
Mushfiqur Rahim is bowled out during the World Cup match against New Zealand in Chennai. AP
Earlier, Mushfiqur Rahim hit a fine half century to lead Bangladesh to 245-9 while veteran Black Caps fast bowler Trent Boult claimed a 200th one-day international wicket.
Mushfiqur made 66 off 75 balls with six fours and two sixes, taking his number of fifties in the format to 48 having also hit a half-century against England three days ago.
The 36-year-old, playing in his 259th ODI, shared a crucial 96-run fourth wicket partnership with skipper Shakib Al Hasan (40) to help their team recover from 56-4.
Mushfiqur was eventually clean-bowled by Matt Henry as he attempted to pick up the scoring rate after Shakib had perished, caught by wicketkeeper Tom Latham off Lockie Ferguson after top-edging an attempted pull shot.
Shakib ended his innings suffering from cramps in the sweltering heat and batting without a helmet or cap against the spinners.
After the game, teammate Najmul Hossain Shanto said Shakib "has gone for a scan" without specifying the injury concern. "We'll then know what's happened to him," said Najmul. Mushfiqur's brother-in-law Mahmudullah, batting at number eight, added a valuable undefeated 41.
Boult, meanwhile, became the sixth New Zealand player to take 200 ODI wickets. "It was pretty hard not to think about the 200th wicket when it was coming up on the screen every day before the match," said Boult. "It's nice to tick it off and on a bigger note nice to keep Bangladesh to a good total and hopefully we can chase it down.
"It's not why you play the game but nice to tick them off along the way. The one-day format is one I've enjoyed down the years. I feel lucky to be here in a third World Cup and contributing like I do."
Boult's 200 wickets in ODIs takes him level with Chris Cairns on New Zealand's all-time list which is topped by spin bowler Daniel Vettori who claimed 297 before he retired in 2015.
The 34-year-old reached the personal landmark when he dismissed Towhid Hridoy, caught at extra cover by Mitchell Santner for 13, in the 38th over.
Playing in his 107th ODI, Boult also dismissed opener Liton Das off the first ball of the match.
Liton was celebrating his 29th birthday but any hopes of a big score to mark the occasion were shattered when he shuffled down the wicket to confront Boult only to sky the ball to a grateful Henry who pocketed the chance at fine leg.
Scoreboard in the World Cup group game between Bangladesh and New Zealand at the M.A. Chidambaram Stadium in Chennai on Friday:
Bangladesh
Liton Das c Henry b Boult 0
Tanzid Hasan c Conway b Ferguson 16
Mehidy Hasan Miraz c Henry b Ferguson 30
Najmul Hossain Shanto c Conway b Phillips 7
Shakib Al Hasan c Latham b Ferguson 40
Mushfiqur Rahim b Henry 66
Towhid Hridoy c Santner b Boult 13
Mahmudullah not out 41
Taskin Ahmed c Mitchell b Santner 17
Mustafizur Rahman c Latham b Henry 4
Shoriful Islam not out 2
Extras (lb1, nb4, w4) 9
Total (nine wkts; 50 overs) 245
Fall of wickets: 1-0 (Liton Das), 2-40 (Tanzid Hasan), 3-56 (Mehidy Hasan Miraz), 4-56 (Najmul Hossain Shanto), 5-152 (Shakib Al Hasan), 6-175 (Mushfiqur Rahim), 7-180 (Towhid Hridoy), 8-214 (Taskin Ahmed), 9-225 (Mustafizur Rahman)
Bowling: Boult 10-0-45-2 (2w), Henry 10-0-58-2 (1nb), Ferguson 10-0-49-3 (2w, 2nb), Santner 10-1-31-1, Phillips 2-0-13-1 (1nb), Ravindra 7-0-37-0, Mitchell 1-0-11-0
New Zealand
D. Conway lbw b Shakib 45
R. Ravindra c Mushfiqur b Mustafizur 9
K. Williamson retired hurt 78
D. Mitchell not out 89
G. Phillips not out 16
Extras (lb1, w10) 11
Total (2 wkts; 42.5 overs) 248
Did not bat: Tom Latham, Mark Chapman, Mitchell Santner, Matt Henry, Lockie Ferguson, Trent Boult
Fall of wickets: 1-12 (Ravindra), 2-92 (Conway), 2-200* (Williamson, retired hurt)
Bowling: Mustafizur Rahman 8-0-36-1 (3w), Shoriful Islam 7.5-1-43-0 (3w), Taskin Ahmed 8-0-56-0 (3w), Shakib Al Hasan 10-0-54-1, Mehidy Hasan Miraz 9-0-58-0 (1w).
Agence France-Presse