The All Blacks coach

Ian Foster cut a slightly tetchy figure on Wednesday. The All Blacks attack coach was not rude exactly. But he was short with journalists.

What was his reaction to Bundee Aki’s ban? Was it good news for New Zealand ahead of their World Cup quarterfinal clash with Ireland on Saturday? ‘‘My reaction to it? I haven’t really got a reaction to it. I’m pretty focused on what we do. But it’s pretty consistent with what we’ve seen at this tournament.’’

What about Andy Farrell? How has Ireland’s defence coach managed to get one over on New Zealand so many times [four victories and a draw in 12 matches coaching England, the Lions and Ireland]? ‘‘I don’t know, you’ll have to ask Andy that.’’

Well, I’m asking you as New Zealand’s attack coach. ‘‘Well, I’m telling you to ask Andy. He just does a job based on what he sees and we do a job based on what we see.’’ Does he mix the pictures up? Scramble? ‘‘You’ll have to ask him. We’ll play what we see.’’

OK, how about Joe Schmidt then? Does the Ireland head coach have a few tricks up his sleeve or have Ireland shown their full hand in this tournament? ‘‘I don’t mean to be rude, but you’re asking me to guess what another coach is thinking. You’ve got to ask him.’’

Nothing out of the ordinary, perhaps. This is World Cup quarterfinal week after all. Tension is running high.

But there is a fascinating subtext ahead of tomorrow’s quarterfinal. Both teams will be losing their head coach at the end of this tournament. Schmidt and Steve Hansen. Two Kiwis, each vying to outwit the other one last time.

Plenty has been made of their rivalry. Less so about who will take over. But it is equally fascinating. One team has already declared who it will be. Farrell was appointed Schmidt’s successor in November of last year, at the same time as it was confirmed that Schmidt would be stepping down.

The other team has not. New Zealand are not announcing who will be following Hansen until after this World Cup. Foster is right at the top of the list. Having been Hansen’s assistant since 2012, the former Waikato first five-eighth has been involved in one World Cup win already. If he can help to bag another in under