KEY POINTS:
The All Blacks have been in charge of the laboratory for most of the year and have controlled the experiments.
But tonight they arrive at Eden Park with the bunsen-burner under them and no way of altering the flame as they tangle with the Wallabies in a winner-takes-all Bledisloe Cup-Tri-Nations double.
If the rest of the season has been developmental and a stuttering series of matches, this international has all the ingredients both sides want in a full-bore interrogation for the World Cup. The All Blacks have been incapable of slowing their rising mistake rate and, after losing 20-15 to the Wallabies at the McG, they are on the edge of shedding the Bledisloe Cup for the first time in five years.
Tonight is all about redemption or angst; there will be little middle ground for those who follow the All Blacks in a year when everything rugby has been geared to their needs.
The selectors have responded by picking their A side and promising they are close to their A-game. But the anxiety has been coursing through the side with coach Graham Henry ordering three secret, unscheduled training sessions during the week at Eden Park to pack in every detail before yesterday's final practice.
"I think the coaches are using this as a World Cup dress-rehearsal because there is a lot of pressure involved in this game and, for us as Kiwis, the Bledisloe Cup is probably the biggest prize, apart from the World Cup, that we play for," hooker Anton Oliver said.
"This is a fabulous chance to have a dress rehearsal to see how we handle the pressure and expectation of ourselves and others on us - all of those things which you can't manipulate."
The All Blacks overcame the travel and heat to outlast the Springboks with a moderate performance in Durban before their efficiency and composure slipped in Melbourne and Christchurch. It has been a spotty Tri-Nations but one which can receive a huge fillip with a strong retort tonight.
"We were embarrassed in the way we played at the MCG, we were disgraced in how we played but the lucky thing is we have a chance to redeem ourselves," said wing Joe Rokocoko.
There has been nothing approaching the standards the All Blacks showed in the Lions series two years ago or against France in Lyon last season. Understandably, they have hidden large chunks of strategies for use at the World Cup but they have also played some messy rugby. They have looked unsettled by the regular team changes, midfield combinations have been erratic and there has been a lack of tempo about their play.
On the other hand, the scrum and lineout set piece has been more assured, the All Black defensive line has been tight and they have attacked the breakdown powerfully.
One concern will be the influence of Welsh referee Nigel Owens who has been chosen for the World Cup but is controlling his first Tri-Nations test. How he copes with the pace and style of the game will be one of the sub-plots of this intriguing international.
For a variety of reasons, the All Blacks permitted the Wallaby forwards to stay in the MCG test and that allowed their backs to conjure up the victory. The recipe will be the same again for the Wallabies. If they gain scrabble and con the referee in the forward tussles, their backline will inflict problems for the Luke McAlister and Isaia Toeava midfield.
The All Black counter has to be forward dominance, tactical kicking from Daniel Carter and a relentless, disciplined approach with the ball. Any more frothy football will be punished. Byron Kelleher has to challenge the fringe defence with his running game on this sudden-death Saturday.