His best fullback option, or his best fallback option?
That will be the puzzler occupying the mind of All Blacks coach Steve Hansen as he nails down an otherwise clear-cut squad to face the dangerous Wallabies in the Rugby Championship and Bledisloe Cup opener in Sydney on August 16.
Every man and his dog outside red and black country accepts that the Highlanders' Ben Smith is now the pre-eminent No 15 in New Zealand rugby, a status confirmed by yet another standout Super Rugby campaign and three highly impressive tests against England - the last two in the custodian's role.
Even Hansen appeared to be wavering towards that reality by the end of the June series sweep, admitting the quietly spoken Dunedin utility would be hard to budge from his preferred position.
But a late-season form resurgence by test No 15 regular Israel Dagg might just have forced a rethink - a scenario Hansen hinted strongly at when he spoke at the end of his two-day mini-camp in Auckland.
Dagg has been the first-choice All Black fullback ever since supplanting Mils Muliaina in 2011, and has been a perpetual class act in the test arena throughout that time. All Blacks coaches are traditionally super loyal to those type of players.
But the rise and rise of Smith has put the spotlight on Dagg who hasn't always been a consistent performer for the Crusaders. When he picked up a knee injury in the opening test against the English, that opened the door for Smith to show he's even better in the black No 15 jersey than the No 14 or No 13 ones.
But with Dagg fit again, and playing very well for a Crusaders team shooting for their eighth Super Rugby title in Sydney on Saturday night, and rising Blues star Charles Piutau also back from injury, Hansen has some decisions to make.
The All Blacks coach admitted the makeup of his back three to face the Wallabies was now a complicated process.
"Izzy is giving us something to think about," said Hansen. "He's playing well again, and Bender has certainly played well enough when he's had his opportunities. So it will be an interesting conversation we have next week."
Don't be surprised if Hansen falls back on the back three that served him so well last year, with Smith on the right wing, Dagg at fullback and Julian Savea rampaging away on the left side.
That would leave Jane and Piutau scrapping with youngster Malakai Fekitoa over a bench spot - a situation that highlights the embarrassment of riches Hansen has at his disposal as he looks to keep alive a record-equalling 17-test win streak.
Smith said yesterday he didn't care where he played.
"It doesn't worry me, I just enjoy being out there. Whatever position that be, hopefully it's part of the team to start with," he said.
For the record Smith hasn't thought about playing sevens in Rio - yet - and said the World Cup was his next major goal. But he did say his Commonwealth gold in Delhi had been a career highlight.
Hansen yesterday said it was important New Zealand Rugby came up with a sensible compromise that allowed both the sevens and All Blacks programmes to achieve their goals.
"The New Zealand public will expect us to win gold in Rio and will expect the All Blacks to win test matches. They have to co-exist, and that's why we have to be smart about how we go about it," he said.
Hansen also confirmed crocked prop Tony Woodcock (shoulder) was likely to get season-ending shoulder surgery.
"The positives are he'll get six or seven months before he has to play again. When you've been on the circuit as long as he has, that's valuable time."
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