All Blacks gearing up to take on South Africa this weekend in Christchurch.

Sir Graham Henry has not held back on his assessment of the Wallabies, labelling them "the worst I have ever seen".

But while the All Blacks prepare to claim another Rugby Championship crown, by beating the Springboks in Christchurch on Saturday night, the plight of their two nearest foes is not something which excites Henry, the former All Blacks coach.

"It's a concern," Henry told Newstalk ZB. "We haven't played South Africa yet, but they got beaten by Australia and they are woeful. I think it's probably the worst Australian team I have ever seen and that's a real worry for the game.

SUPPLIED Sir Graham Henry has laid into the Wallabies and Springboks.

"You want Australia playing rugby and you want Australia playing well. And you want South Africa to be doing the same thing. But South Africa have probably lost half of their tests over the last three years."

READ MORE:

* ABs v Boks: test preview

* Ex-AB remembers old Bok battles

* Ardie Savea expects tough start against Boks

* Springboks make two changes to pack

* Eddie Jones accuses NZ of controlling rugby world

* All Blacks: 5 talking points ahead of the test

* Jones: ABs are flawed

* Ardie Savea starts against Boks

* Jake White fears for future of South African rugby



Henry said in the interview that world rugby needed both teams to be competitive to create interest in the game and bring in crowds.

STACY SQUIRES/FAIRFAX NZ. Springboks captain Adriaan Strauss fields questions on how to beat the All Blacks ahead of their Christchurch test.

The All Blacks have not lost in 14 tests, and are unbeaten at home in 43 matches since 2009. Coach Steve Hansen has only tasted defeat three times since he took over from Henry after the 2011 World Cup.

That is not expected to change tonight, with the All Blacks $1.04 favourites to beat the $9 Boks.

Henry told Newstalk ZB he wondered whether the All Blacks could step up another level after Richie McCaw and five other test centurions retired after the 2015 World Cup.

But they have been "phenomenal".