Jerome Kaino's departure to Japan leaves a big hole in the All Black ranks and most people are picking the Highlanders' Adam Thomson to be an automatic replacement. Or maybe Victor Vito. I'm not so sure.
There are a few issues to be considered when you are trying to plug a gap the size that Kaino leaves. He is one of the world's best players, never mind loose forwards.
He also brings a physical, hard approach - particularly on the tackle and at the breakdown - that neither Thomson nor other contenders such as Liam Messam and Vito have. Also, we have heard before that the time might be fast approaching for Richie McCaw to move to blindside flanker or No 8. Kieran Read is still playing very well at 8 - so I don't think the All Blacks' brains trust will move him.
But they might look at Richie shifting to 6 - which means the replacement for Kaino could well be a No 7. If we are going to replace a 6 with a 6, my pick will surprise some people - the Hurricanes' Brad Shields.
This bloke has impressed me, not just because he is in form but also because he seems to have qualities that will serve him well at the next level.
He's big - about 1.93m and about 110kg or so - and he hits hard and, even more importantly in today's game, he knows where the ball is.
When he came off the bench against the Blues, he made an immediate impact.
He picked up about four key turnovers and he clattered about like he'd been born to the task. I know many of you will go: Whoa, he's only been around for five minutes. But sometimes you have to back form and back promise.
I know he is only 20 - he turns 21 tomorrow - but that means he will be 24 or so when the next World Cup rolls around and should be at peak.
That's if I am right and he has got the goods at All Black level.
You never know until you try them out at that level, of course, but sometimes what seems a shot in the dark turns out to be an inspired choice. I am thinking of John Hart and John Kirwan, for instance.
I'm not saying Shields compares to Kirwan - not yet, anyway - but he seems to have something extra.
Of the other contenders, I think Messam is a wee bit under-rated as he hasn't made the most of his opportunities as an All Black, though he is a very good Super 15 player.
I'd say the same about Thomson - he has played well at times without quite persuading us that he should play ahead of the likes of Kaino, McCaw and Read and, again, he is very good at Super Rugby level.
On current form, Vito is probably the best of those three and has the added value of being able to play No 8 but, again, hasn't quite impressed enough. If McCaw was to switch to 6, then we'd be looking at a No 7 - and the likes of Matt Todd, Jack Lam and Sam Cane come into play. I think we'd be looking in that direction rather than at some of the 7s tried already - like Tanerau Latimer and previous promising players like Karl Lowe.
Todd was nearly an All Black last year and should be in the running again; Lam has had a good season so far, though Cane has gone backwards a bit at the Chiefs. That's why you can't be too strong about the likes of Shields - Cane, after all, was heralded as the new Richie McCaw in some quarters last year.