Daniel Carter is a classic red-flag athlete. He ripped his groin in 2011 and hasn't really had any luck since. Both 2012 and 2013 were massively disrupted by injuries and, after six months off this year, he broke a leg a month into his comeback.
Aaron Cruden is as tough as they come but, at 82kg, he's vulnerable to injury every time he plays. He had to limp out of the World Cup final and, given the volume of traffic that runs down the No10 channel these days, it's a toss of the coin whether the likes of Carter and Cruden will make it through a test in one piece.
That's why the selection of Beauden Barrett, who earned his first start in the No10 jersey last night, was the big talking point of the week. The All Blacks have reached the enviable position of having three first-fives who would, without question, walk into any other international side.
But the selection that was perhaps more important than Barrett was Colin Slade on the bench. If the worst happens in England next year, it could be Slade called in to save the day.
The Crusaders first-five has a bit of test experience but could do with more. To have him involved now is no bad thing.
If the All Blacks can perform seamlessly with their fourth-choice first-five on the field, they will be in supreme shape to retain their title.
The other key selection last night was Jeremy Thrush, who was thrust into the action at lock 25 minutes into the test after Sam Whitelock was forced off with injured ribs. Luke Romano, Patrick Tuipulotu and Dominic Bird are injured but Hansen could click his fingers and bring in Thrush to provide the scrummaging solidity he felt the All Blacks would need against Argentina.
It's the fact the All Blacks can go outside their 31 with such ease that gives them confidence. Their true strength is not just the quality they have in the squad, but the quality that sits just outside it.
Ryan Crotty, who played so well in Auckland before damaging his jaw, is another not actually in the 31. He'll slip further out of the running when Sonny Bill Williams returns but, while that will be tough on him, it will leave the All Blacks in the enviable position of knowing that if catastrophe strikes at the World Cup and they lose two world-class second-fives, they can call in a player as good as Crotty. It's the same at loose forward where the first cab off the rank is Victor Vito.
It might be hard to fathom right now that the likes of Slade and Thrush could become the big stories at the next World Cup.
It's hard to see disaster striking so hard in one position as it did at the last World Cup.
Hard, but not impossible.
The next tier
Prop: Jeff Toomaga-Allen.
Hooker: Nathan Harris,
Motu Matu'u.
Lock: Jeremy Thrush.
Loose Forward: Victor Vito,
Luke Whitelock, Liam Squire,
Shane Christie.
Halfback: Andy Ellis.
First-Five: Colin Slade, Tom Taylor.
Midfield: Ryan Crotty.
Outside Backs: Patrick Osborne, Frank Halai
