Rugby: All Blacks coach Steve Hansen won't trade verbal blows with Warren Gatland

However much Wales coach Warren Gatland may want to induce a rise out of Steve Hansen this week, it isn't going to happen.

There will be no, or at least little, verbal sparring between the two heavyweight coaches.

The All Blacks arrived in Cardiff on Sunday night local time sore and bruised but ultimately content that they were able to come away from Edinburgh with the win.

It wasn't the performance they wanted against the Scots, but it was the result and from that, the All Blacks have taken ample confidence they can see out their season with a bang rather than a whimper.

They will be facing a Welsh team that struggled past Georgia, but with 13 changes having been made from the team that played Australia the previous week, that was maye to be expected.

And besides, if there is one thing the All Blacks have learned in recent weeks, it is to never believe that the team they are playing won't be able to rise above any form slumps or bridge over any gap in confidence.

The All Blacks fully expect to be facing an organised, disciplined, motivated and skilled Welsh team at the Millennium Stadium.

That's enough reason in itself for Hansen to steer clear of getting involved in any slanging match with his old sparring partner.

There is plenty on which he should be focusing this week and it doesn't include finding time to get involved in a slanging match with Gatland who has made an invitation of sorts for such a duel to break out.

Gatland, who is clearly nursing a simmering resentment and bitterness about the way he perceives he was treated while coaching the Lions in New Zealand, has claimed in his new book that he is in possession of explosive revelations that could damage the All Blacks if they were made public.

He only wrote that they are up in his safe deposit box so to speak, waiting to be cashed in only if he feels he needs to defend himself against dirty All Blacks tactics...whatever that means.

Of course there is ample media intrigue as to what Gatland claims he knows. These days anything salacious tends to dominate social media and is therefore hard currency.

But presumably if Gatland actually knew of any damaging revelations: if he really does know some dark secrets from within the All Blacks camp, he'd have spilled the beans?

The embittered don't typically make threats, they use the weaponry they have to exact revenge: chuck the grenade and walk away.

So it would be a surprise if Gatland actually has what he says he has and instead the line in his book was designed to help a somewhat bland and unrevealing tome sell more copies, and/or rile up Hansen.

And of course, Hansen knows that's exactly the intention which is why he isn't going to get drawn in.

The questions will come about what does he think of the book, but the answers won't. It's a no-win situation to get involved.

To deny Gatland's claim would be to give it credence. It would look defensive and inevitably spark counter claims that the All Blacks really do have something to hide.

He doesn't have any need to defend his players and team culture against accusations that haven't quite been made.

Best to let the whole business float in the ether - ignore it and leave it up to Gatland as to whether he wants to up the ante and substantiate or at least clarify exactly what he meant when he used the word explosive in regard to what he knew about the All Blacks.

The All Blacks haven't finished a season with a commanding performance since 2014. As fate would have it, that was the year they finished with a good win against Wales in Cardiff.

Repeating that this time would be a more effective riposte to Gatland's book and obvious need to feel he's struck some kind of meaningful blow on Hansen and his All Blacks.