Shakib & Mahmudullah share record 224-run partnership
They combined with Bangladesh at 33-4
Both men complete centuries
NZ fell from 152-2 in 30th over to 265-8
Mosaddek took 3-13, Taskin 2-43
Taylor top-scored with 63, Williamson 57
Highlights on BBC Two at 23:50 BST (UK only)
Guptill 30, Ronchi 16
Short, wide, given the treatment from Guptill as Mashrafe strays off line. It seems to be quite dark out there but the sky looks lighter than I've seen for a while. Ronchi makes a bit of room for himself and tries to go the Guptill route but he's given himself too much space, and ends up patting the ball away for a couple.
Jeremy Coney
Ex-New Zealand captain on Test Match Special
New Zealand will appreciate that the pitch has good pace in it. They like to be able to play their shots and get into the drive. They don't want the surface to be slow and the ball to grip.
Unsurprisingly, that flurry from Guptill has brought about a bowling change. Here's Taskin Ahmed - and he beats Guptill first ball! A big drive from Guptill, quite poised, and he was through the shot too early. A single brings Ronchi on strike and he smashes the ball through the infield for four with a nicely-timed drive, the ball striking the meat of the bat. This outfield is still quick, despite the rain.
Jeremy Coney
Ex-New Zealand captain on Test Match Special
New Zealand have got the run-rate up. They have made a statement and now the slip is moving out of place.
Guptill 24, Ronchi 7
Mashrafe doesn't look best pleased after being tonked for six, and he's even less impressed when his second delivery gets slapped to the boundary. New Zealand need someone other than Williamson to step up today, especially after opting to bat first. That's a good response from Mashrafe, line and length, and Guptill can only sneak another single.
Hello! That is magnificent from Guptill. Down the pitch, a big swing of the arms, and the ball flies over the sightscreen and probably into the River Taff. A steward has gone to look for it - I suspect that's a futile task. A beautiful shot.
Jeremy Coney
Ex-New Zealand captain on Test Match Special
There's magic in Mustafizur's fingers - he has so many variations.
A cracker of a delivery from Mustafizur, drawing Ronchi into a loose push forward, and the ball inches past the outside edge and into Mushfiqur's mitts. That's wide from the bowler and Ronchi times the pants off it, driving over the field and down to the boundary. Lovely stuff - that's good timing and placement.
Jeremy Coney
Ex-New Zealand captain on Test Match Special
Mashrafe Mortaza is bowling short of a length and keeping a nice, tight line. I just think he needs to have an extra slip in place because Martin Guptill might make a mistake.
Do let us know where you're listening and reading from today, and also your thoughts on today's game or this competition as a whole. Mashrafe has found his rhythm very quickly this morning. Guptill keeps trying to clip him off his pads, drawn onto the front foot, but he's got no width to play with. That's a maiden, and a very good one at that.
Dan Norcross
BBC Test Match Special
I was sent down to have a look at the pitch and I reported back that it had a green tinge. Yet I'm colour blind so not a reliable witness.
Guptill 12, Ronchi 0
Ooh, that's the first boundary of the day, and it's a streaky one from Guptill! He threw a drive at Mustafizur and the ball hovered in the air for a while, just beyond a diving point's outstretched hand. That's a much better shot though, a more controlled splice that splits the field for another four. Mustafizur drags his line back slightly and bowls into the batsmen's body to keep Ronchi quiet.
Jeremy Coney
Ex-New Zealand captain on Test Match Special
Martin Guptill is an aggressive kind of player. He's one of the big triumvirate for New Zealand.
Mashrafe has decided that he liked England's tactic of going short to New Zealand's batsmen. Martin Guptill, tall, poised, pats the first ball off his hip and Mushfiqur has to dive behind the stumps to cling on. A thick outside edge hovers in the air for a second but there's only one slip - which, to me, seems odd with a new ball - and Guptill gets the first runs as the ball trickles away down to third man.
Vic Marks
Ex-England spinner on BBC Test Match Special
Luke Ronchi is given licence to play his shots, and will be expected to play like that, but the nature of the competition brings extra pressure. It will be in the back of his mind that if he fails, there's not another game in a five-match series to come off in instead.
There's blue sky! It's hovering over a sparse crowd, who are still giving off plenty of noise. It'll be Mashrafe Mortaza to open the bowling for Bangladesh.
New Zealand's national anthem is a tune and a half. Luke Ronchi and Martin Guptill have nipped off to get padded up, while Bangladesh's opening bowlers are twirling their arms over. We're going to have some cricket!
The teams are out for the national anthems. There's plenty of red and green shirts in the crowds - the Bangladesh fans have been awesome throughout this tournament.
Jeremy Coney
Ex-New Zealand captain on Test Match Special
This New Zealand team, as it stands, is in need of surgical repair. There would still be a lot of surprise back home if they were knocked out by failing to beat Bangladesh though.
It looks a bit muddy, but we're reliably informed by Dan Norcross that your foot won't go through it...
Allow Twitter content?
This article contains content provided by Twitter. We ask for your permission before anything is loaded, as they may be using cookies and other technologies. You may want to read Twitter’s cookie policy, external and privacy policy, external before accepting. To view this content choose ‘accept and continue’.
BBC Sport app users may need to click 'view more' to see the above content