Ryan Crotty took the middle chair at the interview table and grimaced for no particular reason. His frown turned upside down when Richie Mo'unga put his right hand on Crotty's neck and started massaging it.

In front of about 50 media at New Zealand's Rugby World Cup news conference.

Asked if he was showing off their tight combination, Mo'unga laughed.

New Zealand’s coach Steve Hansen speaks during a press conference to name his side ahead of the Rugby World Cup in Japan, in Tokyo Thursday, Sept.19, 2019. New Zealand will play against South Africa on Saturday, Sept. 21 in Yokohama. (Tsuyoshi UedaKyodo News via AP)

New Zealand’s coach Steve Hansen speaks during a press conference to name his side ahead of the Rugby World Cup in Japan, in Tokyo Thursday, Sept.19, 2019. New Zealand will play against South Africa on Saturday, Sept. 21 in Yokohama. (Tsuyoshi UedaKyodo News via AP)

"There's other things we do," he said, teasingly and to much mirth, "like coffees, catchups ... not just neck rubs."

This was Mo'unga taking charge, just as his backline mate Crotty and the rest of the All Blacks expect him to against South Africa in their blockbuster opening pool game on Saturday when New Zealand begins its World Cup title defense in Yokohama.

Mo'unga was picked at flyhalf — or first five-eighths in New Zealand's rugby vocab — while Beauden Barrett, the incumbent who was world player of the year as the flyhalf in 2016 and '17, was kept at fullback. Meanwhile, Ben Smith, regarded as New Zealand's best fullback, was selected among the reserves.

The selections on Thursday confirmed the dual playmaker model the All Blacks unveiled in July in the Rugby Championship test against South Africa, and against Australia twice, was no longer an experiment. It hasn't been an outright success, either. The All Blacks have a win, loss, and draw in those matches.

"Right now he's the person leading our team," All Blacks captain Kieran Read said of Mo'unga's selection at No. 10.

"We want to see him keep continually pushing us. First five, they're the ones that drive it, doing most of the talking and the direction on the field. He's really grown into that part of his game and I can't wait to see him on the field on Saturday."

Read has been playing with Mo'unga for six years, starting with Canterbury, then the Crusaders for three years, and the All Blacks for the last 15 months. They have a cupboard full of trophies together.

"He doesn't appear to be nervous," Read said. "He's always happy to have a joke, to joke around, and a smile on his face. For him, the more relaxed he is, the better performance he puts out."

Mo'unga wasn't nervous on Thursday. He says he can't wait for his World Cup debut along with 11 others in the All Blacks' 23, and will take a moment for himself in front of the sellout crowd of 72,000 in Yokohama Stadium.

"I'll soak it up," he said. "I'll be out in the middle of the field just looking around and thinking, 'Wow, what an amazing time to be here,' but knowing in the back of my head I have a job to do and the team needs me to do my role well. It's being clear about our game plan and what we're trying to achieve so I can boss the boys around."

Two more Crusaders are on the wings: Sevu Reece and George Bridge, who have eight caps and nine tries between them. With Smith in the reserves, there was no room for wing Rieko Ioane, who has 23 tries in 26 tests.

"These two young fellas have hit the track running and are playing extremely well," coach Steve Hansen said. "Rieko had a bit of a flat patch, which happens in everyone's career, and his job now is to wait for an opportunity. He was going to get one against Tonga (in the last warmup) but unfortunately he had a calf niggle and we didn't play him."

Crotty and Anton-Lienert Brown were in midfield, with Sonny Bill Williams in the reserves. The All Blacks had to deny this week that Williams had a tournament-ending knee injury; he's not starting because he hasn't played much in six weeks, and Jack Goodhue was sore and not to be risked.

"There's been a lot of talk about how we've never settled on a combination," Hansen said, "but I think the versatility of this group allows us to play whoever we want and the combination clicks. People are used to seeing a Ma'a Nonu and Conrad Smith-type combination but if you reflect back, we used people to change that up. The (2015) final is a great example. We swapped Conrad out at halftime and Sonny came on. The combination now has got to be more than just two people, they've got to be your whole team."

Scott Barrett returns from suspension and will combine with Sam Whitelock in the second row. Brodie Retallick, their main lock who dislocated his shoulder against the Springboks, was "going pretty good at training," Hansen said, without elaborating.

The match will likely decide the winner of Pool B. The top-placed team then has a good chance of avoiding a quarterfinal against No. 1-ranked Ireland.

Hansen said the last two weeks feel like they have dragged, and he's glad the match was almost here.

"To play this opponent first, we couldn't ask for anything more," he said. "It's exciting. Whilst it doesn't look on my face, it is."

New Zealand: Beauden Barrett, Sevu Reece, Anton Lienert-Brown, Ryan Crotty, George Bridge, Richie Mo'unga, Aaron Smith; Kieran Read (captain), Sam Cane, Ardie Savea, Scott Barrett, Sam Whitelock, Nepo Laulala, Dane Coles, Joe Moody. Reserves: Codie Taylor, Ofa Tuungafasi, Angus Ta'avao, Patrick Tuipulotu, Shannon Frizell, T.J. Perenara, Sonny Bill Williams, Ben Smith.

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