Jimmy Cowan has vowed New Zealand will not shirk the physical confrontation in their crucial Tri-Nations clash with South Africa this weekend.

The All Blacks came off second best against the Springboks in successive losses in South Africa as their opponents' brutal defence and physical aggression at the breakdown put the New Zealanders back on their heels and the enormous pressure they were under resulted in two error-strewn displays.

The feisty scrum-half is looking forward to making amends for those sub-standard performances in Bloemfontein and Durban when the two teams meet again in Hamilton on Saturday.

"Over the last two Tests we sort of got away from trying to confront them really and were trying to look for space and we did some silly kicks in our own half.

"This week, I don't want to give too much away, but we're going to meet fire with fire and see what happens," Cowan said.

"They are classed as the world champions at the moment and they've every reason to be. But it makes the challenge even more important this week.

"It's one we're looking forward to and I just want to get out there and mix it up really."

Captain Richie McCaw admits the All Blacks' pride - particularly that of the forwards - had taken a hit in South Africa.

"You never like to be beaten in that area. There's no doubt that that's where we were a bit disappointed the last time," the skipper said.

"Their tight five certainly created a pretty good platform for them to operate with.

"Everyone realises that's got to take a step up and the Wallabies showed that when you do that you can put them under a bit of pressure.

"We are lucky we've got a chance to get that sorted."

The Springboks were flat against the Wallabies in Brisbane and looked tired in the second half as the Wallabies powered their way to a convincing 21-6 win.

But McCaw doubted whether fatigue had started to set in for the world champions who have largely stuck with the same forward pack throughout the series.

"They definitely weren't as up for the game last week as they were the week before but I'm certain that they will have that sorted for their last game for a while this Saturday.

"The Wallabies were desperate and they were really physical and got stuck into them and forced them into mistakes.

"That's a lesson for us that the physical battle is pretty important in these Tests as to how you play.

"They showed that if you put them under pressure they (South Africa) will make mistakes just like anyone else and that's what the Wallabies did."

New Zealand head into the match at Waikato Stadium knowing they need to earn a bonus-point win if they are to keep their chances of retaining the trophy alive.

But McCaw said getting the four tries to secure that bonus point was of secondary importance to the performance of the team.

"If you go in there saying 'we've got to score four tries' you don't actually look at the process of what you've got to do," he explained.

"We've got to go in, get our performance right and if we do that we'll create opportunities and we've got to take them.

"You don't want to cost the game by throwing the ball around and trying to score a try.

"That, I believe, comes second to getting our performance dead right. If we do that then I'm sure we'll have the opportunity (to score tries)."

A bonus point could be enough for South Africa, who don't arrive in Hamilton until Thursday afternoon, to claim their first Tri-Nations title since 2004 and All Blacks assistant coach Steve Hansen believes preventing that is the key.

"We can chase a bonus point as much as we like but if they get one it's over anyway," he said.

"The key thing for us is that South Africa don't get a point and we win."