Who is going to the Rugby World Cup? Breaking down the All Blacks final 31

The All Blacks will name a 31-man squad to head to the World Cup in Japan. Photosport

World Cup selection is the most coveted of them all.

It's why those who today receive phone calls, prior to the 31-man All Blacks squad unveiling at Eden Park, will need time and space to process their immense disappointment.

For those on the cusp who miss the cut, it will be among the most difficult moments in their careers.

Many in New Zealand's knowledgeable rugby public could pick the vast majority of the All Blacks squad that seeks to capture a third straight crown but, at this juncture in particular, Steve Hansen plays his cards close to his chest and invariably springs a surprise or two.

World Cups are won by an experienced core but there is always room for a late form horse.

Ahead of today's reveal we break down the big decisions the All Blacks selectors Hansen, Ian Foster and Grant Fox, would have grappled with.

Front-row:

Owen Franks' scrum dominance and defensive work around the fringes has waned in his 32nd year but it would be a major surprise if the All Blacks discard their most experienced prop on the eve of the tournament.

Hansen has been strong on the intent to take mobile front-rowers to Japan – those who perform core duties while also getting around the park to make repeat tackles and handle the ball under pressure.

Emphasis on these traits saw cult figure Karl Tu'inukuafe fall out of favour this year, and probably leaves a choice between Angus Ta'avo and Atu Moli for the fifth propping spot.

Possible props: Owen Franks, Joe Moody, Nepo Laulala, Ofa Tu'ungafasi, Angus Ta'avao

Hookers:

Dan Coles and Codie Taylor, the dual Horowhenua-Kapiti products, pick themselves. Highlanders rake Liam Coltman is the big mover this year with his strength over the ball pushing Nathan Harris out of the frame. Harris then suffered an injury for Bay of Plenty which required surgery.

As it is, the choice comes down to Coltman, who endured poor lineout throwing in Argentina, and Wellington's dynamic but inexperienced prospect Asafo Aumua.

Possible hookers: Dane Coles, Codie Taylor, Liam Coltman

Locks:

Brodie Retallick's dislocated shoulder complicates matters. Hansen has previously favoured stacking his loose forwards in favour of carrying only three specialist locks but with Retallick expected to be included - and unlikely to be fit until the quarterfinal stage - immediate cover will be required.

The final decision hinges on whether the All Blacks desire versatility in the form of Jackson Hemopo or Vaea Fifita, both of whom can swing between lock and blindside, or Patrick Tuipulotu's physical, specialist presence in second-row. Given his recent performance against the Wallabies at Eden Park, Tuipulotu would appear to have the inside running.

Possible locks: Sam Whitelock, Scott Barrett, Brodie Retallick, Patrick Tuipulotu/Hemopo

Loose forwards:

Three specialist opensides seems a luxury and so it will be interesting whether the All Blacks opt to squeeze Matt Todd alongside Sam Cane and Ardie Savea, the latter admittedly adept at in all three loose forward roles.

While Todd brings energy and mobility, he could leave the All Blacks undersized against larger packs.

Liam Squire's expected inclusion will provide the major talking point after his self-imposed exile during the Rugby Championship.

Squire's dominant presence, both with ball in hand and in his front-on defence, changes the dynamic of the All Blacks' back-row options but his brittle body often suffers the strain of his combative approach, and so additional cover may be needed.

Shannon Frizell and Fifita, the latter understandably struggling after the death of his younger brother in a river accident recently, did not do enough this year to nail the starting blindside role in Squire's absence.

That leaves Hemopo and Waikato's impressive young buck Luke Jacobson as possibilities to sneak in.

Possible loose forwards: Kieran Read, Ardie Savea, Sam Cane, Liam Squire, Matt Todd/Jacobson

Halfbacks:

Aaron Smith and TJ Perenara provided the All Blacks their one-two punch over the past four years but after forcing his way past Te Toiroa Tahuriorangi there is a real sense Brad Weber could be ready to seize his chance on Japan's hard and fast tracks, should it come.

Possible halfbacks: Aaron Smith, TJ Perenara, Brad Weber

First five-eighths:

The All Blacks are expected to gamble, somewhat, by taking only Beauden Barrett and Richie Mo'unga to Japan. In a tense finish they opted not to hand Highlanders playmaker Josh Ioane his test debut off the bench in Argentina, and will probably feel Jordie Barrett can cover No 10 for the lesser pool matches.

Possible first-fives: Beauden Barrett, Richie Mo'unga

Midfield:

Sure to be another hot topic, with Ngani Laumape widely expected to miss the cut. If that proves the case, Laumape must rank among those most unfortunate. Any other test nation would love to utilise his line-breaking power, acceleration, top end pace and try-scoring nous but with only four spots available, the experience of Sonny Bill Williams and Ryan Crotty, set to make his return for Canterbury after two months out with a broken thumb this weekend, are likely to be favoured.

Possible midfielders: Jack Goodhue, Anton Lienert-Brown, Ryan Crotty, Sonny Bill Williams

Outsides:

A real blend of youth and experience, form and those struggling, may board the plane. Talk of axing Ben Smith appears far too premature, given he is still making his way back from a hamstring issue. Pressure is, however, mounting on Smith and Rieko Ioane to front after standout performances from George Bridge and Sevu Reece in the last test against the Wallabies. Jordie Barrett's versatility, long-range goal kicking and raking punt is likely to leave Braydon Ennor the main casualty from this area.

Possible outsides: Ben Smith, Rieko Ioane, Jordie Barrett, George Bridge, Sevu Reece