The All Blacks' selection picture at No 10 may not be quite what it seems. For all that it may appear to be a choice between Aaron Cruden and Beauden Barrett, it's probably more a battle between Cruden and Lima Sopoaga.
These two are out-and-out No 10s and the All Blacks selectors need to determine, given the versatility of Barrett and to a lesser extent Damian McKenzie, whether they can accommodate two specialist first-fives in their 32-man squad.
To make that call, they need to know their pecking order and be sure which of Cruden and Sopoaga they would deem their first choice. This is why there is a fair bit riding on events in Hamilton tomorrow night.
These two will face each other and provide a better picture for the All Blacks selectors about how each man is tracking. Whatever thoughts they have about a first-five pecking order will be challenged.
It's not really about how Cruden and Sopoaga operate in a head-to-head capacity - more how they respond to the pressure of the occasion and drive their respective teams around the field.
What will interest the selectors is how much influence each man can exert, the way they respond tactically to the ebb and flow of the game, and how well they maintain their clarity and accuracy.
It's a big game - as good a replica of test football that can be had - and while the panel forms its views over a period of time, these local derby encounters provide more valuable reference points.
The assumption would be that Cruden is leading the race to wear the All Blacks No 10 shirt in the first test of 2016. His claim to a starting spot feels like it's the strongest.
He brings the most test experience of any of the aspiring first-fives. He's been a test footballer since 2010 and in those extended periods when Daniel Carter was injured between 2012 and 2014, Cruden established that he too is a world class player.
His case to start is not built exclusively on history, either. He's played well this year - been lively when he's run and mixed his options well.
Sopoaga can't compete on track record. He's played just the one test but did look composed and confident in a rare victory at Ellis Park - one of the more intimidating venues on the planet.
His natural authority and decision-making in the knockout rounds of Super Rugby last year were impressive and made a strong impression on the selectors. Sopoaga went from rank outsider to being on the verge of World Cup selection, although he ultimately fell just short of making the tournament squad.
But he hasn't been at that level this year. The Highlanders haven't flowed the same way and Sopoaga's influence has been harder to determine.
The one area where he's pushed ahead of Cruden and Barrett is in his goalkicking. He's sitting on a 78 per cent success ratio this season which compares with 64 per cent for Barrett and 55 per cent for Cruden.
There is potentially room in the All Blacks squad of 32 that will be announced on May 29 for Cruden, Barrett, McKenzie and Sopoaga.
Potentially but not definitely, and Sopoaga, who is unlikely to do enough to usurp Cruden as the first choice No 10, has to play well enough to convince the selectors he's worth having inside the camp where he will be able to advance his education and stay in touch with the All Blacks game plans and attacking philosophies.