New Zealand head coach Steve Hansen is confident his team has what it takes to win an unprecedented third straight Rugby World Cup title, but for the moment he is looking no further than Saturday's monumental opening clash against archrival South Africa.

"I'm as confident as you can be," Hansen said on Friday, when asked if the All Blacks can add a record fourth World Cup title to their name in Japan. "I think we've got the talent in the group to get the job done. It's just whether we earn the right to get all the way there.

"The key thing is we know we get the same amount of good luck and the same amount of bad luck as everybody else. It's what we do with it when it happens and how we react to it when it's negative. That'll be important but we've certainly got the talent to get the job done."

New Zealand opens its Rugby World Cup campaign in Yokohama against two-time champion South Africa, with the two teams heavily tipped to meet again in the final at the same venue on Nov. 2.

South Africa's fortunes have been revived under coach Rassie Erasmus after several years of poor performances and chastening results, with the Springboks winning this summer's shortened Rugby Championship and drawing 16-16 with the All Blacks along the way.

Captain Siya Kolisi is eager to test how far his team has come, and said there was "no better way to start the tournament" than Saturday's heavyweight encounter.

"They were quite dominant before the past two years, and then we had to fight back as a team to make sure we got a little bit of respect back," said loose forward Kolisi. "That's what we've been working on the past couple of years. I think we're in a good place at the moment and the rivalry is the best it's been for a while. I'm looking forward to the game. We've worked hard. We'll give them the respect that they deserve, but all that we can sort out is ourselves."

South Africa finished fourth at the 2015 Rugby World Cup in England but then went on to win only 11 of their next 25 test matches, including a first-ever loss to Italy and a record 57-0 defeat to the All Blacks.

Erasmus has turned the Springboks around since taking over in March 2018, and Hansen is not expecting a repeat of that historic September 2017 whitewash.

"That was a one-off, and a remarkable performance on a night when everything went well for us and not so good for them," said Hansen. "Prior to that, I thought the games had been reasonably close. Rassie's come in and he's worked really hard on what they're trying to do defensively and on their fitness. I think they're the two key things."

Hansen raised eyebrows in New Zealand by switching star flyhalf Beauden Barrett to fullback and bringing Richie Mo'unga into the No. 10 position for this year's Rugby Championship, and the coach has stuck with the dual-playmaker formula for Saturday's game.

Mo'unga will be making his World Cup debut at International Stadium Yokohama, but Hansen has no doubts that the 25-year-old is ready.

"We wouldn't be picking him if we didn't think he was ready," said Hansen. "He plays some scintillating rugby at times. He's good with the ball in hand, he's got pace, great kicking game, good vision. He's got all the attributes to be a wonderful, wonderful player. He's now just got to go and do it on the highest stage.

"He's got the mental fortitude to just want to jump out and announce himself come Saturday. He follows in the footsteps of some greats. He's playing with one of the current ones who's playing at fullback. He's got plenty of support."

Saturday's Pool B game has been billed as a battle to avoid a tougher route to the final, with the second-place team in the group earning a quarterfinal place against the winner of Pool A — comprising Ireland, Scotland, Japan, Samoa and Russia.

Kolisi gave that theory short shrift, refusing to look further than Saturday's opener.

"This game is big enough by itself," said the 28-year-old. "We're just going to give it our best and then after the game we'll see what happens. It doesn't matter who you play because you have to beat anybody in your way anyway. You're going to meet a strong opponent, even if you don't meet it in the quarterfinals. Anyone who plays in the quarterfinal shows you how hard they've worked and how good they are to get there."