Sonny Bill Williams' omission against Argentina this weekend prompts the question of just how much injury-proneness will play a role in All Black selections for the coming World Cup.
As his detractors remind anyone who will listen, SBW has suffered the odd injury or two hundred. He is the Kiwi equivalent of former Tottenham Hotspurs and England midfielder Darren Anderton who could pull a muscle making a cup of tea, earning the cruel nickname "Sick Note" after being almost constantly sidelined by injury.
But the selectors' clear desire to have him in the World Cup squad could affect the make-up of the midfield, area of hottest competition along with props and loose forwards.
We're talking Ryan Crotty. The selectors would love to have room to take him to Japan; his decision-making, the lines he runs, clever passing and instinctive support play are hugely respected.
But, if SBW is on board, Crotty's tendency to suffer concussion may count against him. The 30-year-old has played 44 tests – and would have played more if not for concussions.
Those protocols will be strictly observed in Japan; if he has a head bang at the same time SBW blows a fetlock, All Black midfield options would be halved. That is not an adjustment the selectors will want to make at the sharp end of a World Cup campaign, particularly with rush defences lining up to repeat previous successes against the All Blacks.
SBW, centre Jack Goodhue and impact player Anton Lienert-Brown seem certainties. Crotty and Ngani Laumape are in direct competition for the final spot, at 12, though the selectors in past years preferred Crotty at 13 when Williams starts at 12 (until Goodhue arrived).
Logic suggests that selectors keen on SBW's ability to offload in tackles – offloads being more difficult to defend – will want a player of similar offloading ability to back him up. That player is Laumape and, though much has been made of his improved communication and kicking skills, it will likely be those offloads and midfield penetration the selectors will focus on when Laumape meets the Pumas' swarming defence.
Crotty is not without hope; if fellow Crusader Braydon Ennor steps up at this level and makes the World Cup squad as a cover for wing and midfield, room could be made for Crotty. However, Crotty is off to Japan to play club rugby after the World Cup – a deciding factor in neck-and-neck selections before (although overlooked when it has suited the selectors).
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The other fascinating element of the test against the Pumas is at No 6, the position made even cloudier by Liam Squire's decision that he did not feel ready for international rugby after his medial knee ligament injury.
There's time for him to come right – and a firing and fired-up Squire would be first choice No 6 – but there is a hint of factors other than ligaments in Squire's decision.
Vaea Fifita starting at 6 against Argentina may persuade some he is winning the battle for a place in a Squire-less scenario. However Shannon Frizell was left in New Zealand because of injury; expect him to figure soon. There's also a bloke on the bench called Luke Jacobson who could yet prevail.
He's been a comer for some time, even if most are only seeing it now. In a 2017 column (looking at candidates if Kieran Read's injuries curtailed his career), I wrote: "If it's youth you are looking for, there will be much interest in the Super Rugby debut of the Chiefs' Luke Jacobson (skipper of the world champion New Zealand under-20s side)."
Though his 2018 debut season was interrupted by injury, this season's campaign gathered real pace. His man-of-the-match performance in the Chiefs' comeback draw against the Highlanders in May alerted many to his international potential.
That night, Jacobson played one of the most compete loose forward games seen for some time. He carried superbly, carving off the most run metres of any forward; he won two turnovers and made a game-high number of tackles, made three clean breaks, beat four defenders and made two offloads. Oh, and scored a try.
He can play all three loose forward positions though he too has suffered from concussion – the latest bout ruling him out of the Super Rugby finals. He and Dalton Papalii (not selected against the Pumas) are facing off for a potential squad spot for someone who can play 6, 7 and 8.
If you accept six loose forwards will be taken to the World Cup, Read, Cane and Ardie Savea are certainties. Add Jackson Hemopo as he covers lock as well as 6 (only three locks are likely to be selected).
Squire would fill one of the two spots left on return. Jacobson could take the other – meaning three players who can play No 8 (Reid, Savea, Jacobson); three who can play 6 (Hemopo, Squire, Jacobson); and three who can play 7 (Cane, Savea and Jacobson). Squire can also play 8.
If you are questioning why all this interchangeability is needed, read Gregor Paul's dissection of how the All Blacks are looking to play two teams in the World Cup pool stages.
It's a testing schedule – and those more inclined to injury could have an extra hurdle to clear this time round.