The World Cup squeeze: Which All Blacks have done enough to make it to Japan?

After four years of meticulous planning, a further four tests in 2019 and a plethora of players coming and going in this World Cup cycle, All Blacks head coach Steve Hansen is primed to name his final New Zealand squad - a 31-player side to take to Japan next month.

Many of the players that are going to be named on Wednesday will have been penciled in to travel to Asia long ago, with the likes of Beauden Barrett, Ardie Savea and Rieko Ioane becoming stars under the tutelage of Hansen since the 2015 World Cup.

Together, with their sublime skill set and Hansen's world-class coaching, the All Blacks remain one of the favourites to win the Webb Ellis Cup, although they aren't unprecedented favourites like they were four years ago when they romped to a second successive world title in England.

Still, they will be tipped by many to return back to New Zealand with a hat-trick of world crowns to their name, but their perceived dominance in the sport doesn't mean all 31 spots in the World Cup squad have been sewn up.

There have been plenty of individuals who have joined Barrett, Savea and Ioane in impressing since this current World Cup cycle kicked off in 2016, which should lead to no surprises being sprung in some positions when the squad is named this week.

For example, Aaron Smith, TJ Perenara and Brad Weber will all board the plane as the country's three top halfbacks, as will first-five duo Barrett and Richie Mo'unga.

Up front, Dane Coles and Codie Taylor continue to jostle for the starting hooker role, making them key members of the team.

They will likely be joined by Otago rake Liam Coltman, although the international rookie looked shaky when he turned out in the Mitre 10 Cup on Thursday, with his lineout throwing again the main concern in his side's 29-21 defeat to Hawke's Bay in Napier.

It would be a shock to see the selectors take just two hookers, though, and Coltman should have done enough this year through his work rate in general play, strong ball-carrying and tidy play at the breakdown all selling points for his inclusion.

Brodie Retallick will also be named despite the fact his dislocated shoulder will probably keep him out of action until the end of pool play or the beginning of the knockout stages.

He will be accompanied by long-time second row partner Sam Whitelock, the industrious Scott Barrett and Patrick Tuipulotu - whose physically imposing showing against the Wallabies at Eden Park a fortnight ago must surely have sealed his place - as the locks.

With four locks being taken due to Retallick's injury, that should likely free up room for five loose forwards, which is where the selection pinch will begin to be felt.

Savea, Sam Cane and captain Kieran Read are all non-negotiable inclusions, while Matt Todd will surely go as one of two bona fide openside flankers alongside Cane.

That would allow for one more loosie - a No. 6 - and Liam Squire's decision to come out of his self-imposed international exile may have just solidified who that final spot will belong to.

The 28-year-old wasn't included in the All Blacks' 39-man Rugby Championship squad after he told Hansen that he "didn't feel ready" for test rugby, with injuries and personal issues ruining his Super Rugby campaign with the Highlanders.

However, he has returned to action emphatically in the Mitre 10 Cup with Tasman, scoring two tries in their opening three games and making a noticeable impact with his typically confrontational style of play.

His form could be transitioned into the black jersey, as Stuff is reporting that Squire wants to return to the test arena in Japan, which paves the way for Hansen to fast track him back into the national set-up.

That would see the demise of Vaea Fifita's, Jackson Hemopo's and Luke Jacobson's World Cup hopes, although Fifita may already be out of contention after picking up an injury prior to Wellington's 23-22 victory over Canterbury on Friday.

Despite being dropped for the Bledisloe Cup decider in Auckland a couple of weeks ago, 108-test veteran Owen Franks should be added as one of five props based purely on experience alone.

He may not fit Hansen's criteria of being a mobile, ball-playing front rower, but he's a hard hitter defensively, anchors the scrum strongly, and cleans ruck after ruck without complaint.

Joe Moody, Nepo Laulala and Ofa Tu'ungafasi are the other certainties in the propping ranks, with Angus Ta'avao seemingly the favourite to edge out test novice Atu Moli after featuring in all four of New Zealand's tests thus far this year.

Fresh from a compelling display in Auckland's 19-13 victory over Bay of Plenty on the weekend, Ioane also shouldn't be dismayed at his culling from the second Bledisloe Cup test.

The power wing joined Franks and fellow outside back Ben Smith as the three high-profile omissions from the All Blacks' 36-0 thrashing of the Wallabies on August 17 after a series of underwhelming showings in the Rugby Championship.

Ioane should have quelled concerns surrounding his form, though, after a rare outing in the Mitre 10 Cup, in which he scored a try and played a key role in setting up another.

Both he and Smith, with his 79 test matches, are too important to the national side to miss out on the World Cup squad altogether, so they, along with Jordie Barrett, whose utility value will be highly prioritised, should all be included.

Joining them in what is set to be an outside back quintet will probably be Crusaders flyers Sevu Reece and George Bridge, with their virtuoso performances at Eden Park in the absence of Ioane and Smith enough to cement their spots in Japan.

It's a harsh call for their Super Rugby teammate Braydon Ennor, who has shown plenty of promise over the past two years and was only given 15 minutes off the bench against Argentina to show what he is made of at this level.

That leaves the midfield, which could be the most intriguing selection conundrum of all.

Like Ioane, Sonny Bill Williams has had many a doubter in recent times, with his storied injury woes at the forefront of discussions revolving around him.

However, his top-class showing against the Wallabies should have confirmed his place in the World Cup squad, meaning he'll join Jack Goodhue and Anton Lienert-Brown as three of the four midfielders in the side, leading to a straight shootout between Ngani Laumape and the injured Ryan Crotty.

While Laumape has been in barnstorming form all year, Crotty's versatility, experience and leadership could be enough to get him across the line.

It may be an unpopular decision to leave the powerful Laumape in New Zealand for the tournament, but when World Cup titles largely depend on experience, don't be surprised to hear Crotty's name read aloud on Wednesday - even after almost two months out of action.

Possible All Blacks squad for World Cup:

Dane Coles, Liam Coltman, Codie Taylor; Owen Franks, Nepo Laulala, Joe Moody, Angus Ta'avao, Ofa Tu'ungafasi; Scott Barrett, Brodie Retallick, Patrick Tuipulotu, Sam Whitelock; Sam Cane, Kieran Read, Ardie Savea, Liam Squire, Matt Todd; TJ Perenara, Aaron Smith, Brad Weber; Beauden Barrett, Richie Mo'unga; Ryan Crotty, Jack Goodhue, Anton Lienert-Brown, Sonny Bill Williams; Jordie Barrett, George Bridge, Rieko Ioane, Sevu Reece, Ben Smith.

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