Welcome to the test which may be the toughest mentally all year for the All Blacks: an opportunity to again represent their country - never to be taken lightly – to maintain or in some cases gain match fitness two weeks out from the World Cup, and an opportunity too to injure themselves and miss the plane altogether.
And that's just for the players, who have already been given the message by coach Steve Hansen and skipper Kieran Read to focus only on what's in front of them at Waikato Stadium on Saturday rather than a potential business class flight on Monday and at least six weeks in Japan.
How successful they are will be obvious in the level of their performance which reached a new and vastly improved state last time out against the Wallabies at Eden Park.
For the coaches it must be just as bad; the equivalent of steeling oneself for an inoculation. They'll know it's good for them but it could hurt a bit too.
Hansen, for example, would have found it extremely difficult to watch the Super Rugby final between the All Black-laden Crusaders and the Jaguares two months ago, so all sorts of feelings must be percolating inside him at the prospect of this test against Tonga.
"You can sense the excitement in all of them and a little bit of nervousness too because it's only human nature that they think about what's coming next," Hansen said. "That's why the message has been really important that 'we are where our feet are' and we're right here right now and concentrating on what we're doing. If we get this job out of the way then we can get really excited."
Ryan Crotty has been operating in a rehabilitation no-man's land since the Super Rugby semifinal due to a broken thumb.
He's known he couldn't do anything to sway the selectors' thinking because he hasn't been playing, but, now that he's been included in the 31-man squad, there is a chance another problem could dash his World Cup dreams in the cruellest way possible. He has never attended a World Cup and will never get another chance.
Not surprisingly, the elephant in the room has been addressed. Injuries are out of anyone's control, but a common saying in rugby, as in all contact (or in these days collision) sports, is that you're more likely to be injured if you are worried about getting injured.
"[Hansen] has addressed it and Reado pulled the leaders aside at the start of the week and talked about that as well," Crotty said. "It's on everyone to prepare for that individually and we peeled it back to the intent we bring.
"It has to come from inside you … that will put forward the performance that we desire. And you can see that intent – that's obvious. We're holding each other accountable."
South Africa are looming in a fortnight, and there are some within the All Blacks who could be playing for a starting position in one of the most pivotal pool games New Zealand has ever played.
Fullback Ben Smith, a possibility to start on the right wing against the Boks, should he find the form against Tonga that has so far eluded him in the black jersey this year, has been told to back himself, to not over-think things, to go with his instincts.
The same applies to his teammates, and the entire Tonga team, for that matter, as they are also on the brink of a trip of a lifetime. It may not be easy for some of them, though.
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