Jonathan Davies: New Zealand's game is hanging on McCaw

They remain the favourites, but I honestly feel New Zealand lost their aura against Argentina.

And now with one of their vital players absent and with the other crucial performer struggling with injury they face the Test of their lives against their neighbours.

For so long Richie McCaw has been the flag-bearer for opensides, but I believe injuries have slowly taken the edge off his play. In fact, if you are naming the best No 7s at this tournament so far he would come in behind David Pocock and Sam Warburton.

Granted, McCaw's one of the greatest and could still produce two performances which would define this World Cup as well as his whole career. But that's exactly what the All Blacks might require from their talisman.

Every team suffers injuries, but they seemed rudderless against the Pumas without the stricken Dan Carter. Piri Weepu, the scrum-half, stepped up to the mark and I think Graham Henry should have picked him at fly-half for this semi-final.

Weepu's played for the Highlanders at No 10, he's going to run the show from No 9 anyway, so you may as well have him in the box-seat to get the outside backs running. Furthermore, Sonny Bill Williams is their most potent game-breaker, but he is only among the replacements so we will have to wait to witness his wicked offloads.

So what's the prediction? Well, certainly the Aussies won't be scared in Auckland, no matter how fortunate they were against South Africa. They will prey on New Zealand tension and try to crank up the pressure to unbearable levels.

Here's a premonition: Quade Cooper has been dreadful as the Wallabies No 10 during this World Cup so far. Truly dreadful. But guess what? He's a Kiwi by birth, with a Kiwi mum and a Kiwi dad. What are the chances of him suddenly discovering his form and knocking out his motherland? It may just be written in a big book somewhere.