And again USA assert themselves in the tackle as Alycia Washington drives Sarah Goss way back into her own half.

But New Zealand have all the possession at the moment, these are long defensive sets from the USA.

All full-back Cheta Emba can do is clear downfield.

The USA have begun well on the turnover front, and there's another one.

New Zealand penalised for not releasing in the tackle after a great break from number eight Aroha Savage.

The Black Ferns are looking formidable in the midfield but USA are matching their physicality so far.

But New Zealand reply immediately through Kendra Cocksedge's penalty from in front of the posts.

Black Ferns taking the points, could they be nervous?

Fiona Hayes
Ex-Ireland prop on BBC Radio 5 live sports extra

You can see just at the end it was almost like a basketball, overhead pass from Cheta Emba to Kris Thomas, and New Zealand got sucked in.

New Zealand look a little bit shell shocked and USA seem slightly more up for it.

Fiona Hayes
Ex-Ireland prop on BBC Radio 5 live sports extra

The USA are really putting it up to New Zealand. You just saw Selica Winiata bundled into touch, which you don't often see.

Victoria Subritzky-Nafatali with the try after just three minutes for the Black Ferns.

But her kicking has been less effective - she's sending the ball right into the hands of USA's best runner Cheta Emba who's taking the invitation with open arms and running at the New Zealand defence.

A Harvard University graduate and a pretty exciting rugby player too.

USA turn down their first shot at points, after New Zealand are pulled for not releasing in the tackle.

And Cheta Emba drives the ball towards the corner.

The Americans have responded well here after conceding an early try.

A brilliant little step from New Zealand flanker Sarah Goss in the midfield, which gets New Zealand on the front foot.

The Black Ferns are showing off here as a a cross-field kick is plucked out of the air by wing Portia Woodman.

But USA get a vital turnover through Naya Tapper - the French wing needs to have another big game if her side are to do anything this afternoon.

New Zealand back in possession and they're already experimenting.

Scrum-half Kendra Cocksedge tries a chipped box-kick, Renee Wickliffe can't run onto it but New Zealand have pinned the USA back in their own half.

Fiona Hayes
Ex-Ireland prop on BBC Radio 5 live sports extra

I think the USA are going to have to pin New Zealand in their 22 - the USA don't want to be playing rugby in their own half.

But not for long.

New Zealand have their first line-out and it's in a dangerous position.

The USA forwards had no answer to the English maul last week, they'll need to perform better today.

Straight away New Zealand kick down USA full-back Cheta Emba's throat and she carries the USA up the half-way line.

Early possession for Peter Steinberg's side.

USA take on the challenge and they get us under way in Belfast...

Slightly more graceful than the All Blacks' haka... and just as intense. How do the USA face up to that?

Singing over and done with, it's time for the haka.

Image source, Rex Features

Right, i'm in place and ready. Are you?

Kick-off is just minutes away in Belfast for the first of the two semi-finals.

It's a huge task for the USA as New Zealand go in search of their fifth World Cup trophy.

Anthems to come...

USA: Cheta Emba; Naya Tapper, Nicole Heavirland, Alev Kelter, Kristen Thomas; Kimber Rozier, Deven Owsiany; Catie Benson, Katy Augustyn, Tiffany Faaee. Stacey Bridges, Alycia Washington, Sara Parsons, Kate Zackary, Jordan Gray.

Replacements: Samantha Pankey. Hope Rogers, Nick James, Abby Gustaitis, Kristine Sommer, Kayla Canett-Oca, Tess Feury, Jess Wooden .

New Zealand: Selica Winiata; Portia Woodman, Stacey Waaka, Kelly Brazier, Renee Wickliffe; Victoria Subritzky-Nafatali, Kendra Cocksedge; Toka Natua, Fiao'o Faamausili (c), Aldora Itunu, Eloise Blackwell, Charmaine Smith, Charmaine McMenamin, Sarah Goss, Aroha Savage.

Replacements: Te Kura Ngata-Aerengamate, Sosoli Talawadua, Aotearoa Mata'u, Rebecca Wood, Linda Itunu, Kristina Sue, Theresa Fitzpatrick, Carla Hohepa