Dan Carter has warned that the job is "not done yet" after ensuring his last game for New Zealand will be a first World Cup final appearance.

The All Blacks superstar made it a case of fourth time lucky after experiencing World Cup heartbreak during previous attempts on global domination.

New Zealand were knocked out by Australia in the 2003 World Cup semi-finals, then they made a painful quarter-final exit to France eight years ago before a groin injury suffered during training meant that Carter missed out on the All Blacks' 2011 world title triumph.

But the 33-year-old is now set to be part of a World Cup final team, with next Saturday's Twickenham showpiece being a 112th and last Test match before he takes up a lucrative three-year contract with wealthy French club Racing 92.

"It's pretty exciting," fly-half Carter said. "You could probably see the emotion after the game.

"It's my fourth World Cup, and I have never been involved in a World Cup final before, so I am pretty excited about that.

"It's not done yet. It is still a huge challenge ahead of us."

"I can't wait to get into training this week and prepare as well as I possibly can.

"It is why we are here - to give ourselves a chance to win back-to-back World Cups.

"And we have given ourselves that chance by reaching the final, but it's not done yet. It is still a huge challenge ahead of us."

Carter delivered an immaculate second-half display as New Zealand navigated their way past a wonderfully resilient South Africa team, landing a drop goal, penalty and conversions of All Blacks tries by flanker Jerome Kaino and substitute Beauden Barrett in a tense 20-18 triumph.

And he admitted it has been a case of "staying in the moment" for him, knowing he could not allow himself to think ahead and dream of reaching that World Cup final goal.

"That has probably been the biggest challenge for me the last two or three weeks is not thinking about the result and outcome," Carter added.

"You can fall into the trap, and I potentially fell into that trap in Cardiff against (pool opponents) Georgia.

"You have a mindset of just nailing each task, staying in the moment, and it has really helped myself and this team, and it is going to have to continue for another week.

"It is quite easy to start thinking about the result and what potentially could happen, but you soon lose track."

New Zealand controlled the early stages of the second half after Kaino had received a yellow card just before the break, with no sense of panic, despite South Africa building a 12-7 interval advantage.

"I think it is the beauty of this side that no-one in that second-half was waiting back," Carter said. "They all wanted to make a statement and help the team.

"The last thing I wanted to do was sit back and wait for something to happen. If I have an opportunity to try and influence the game and the team, then I try to do that.

"There were a couple of key moments in the second half that I think we won. In these important games, they come down to only one or two moments, and we took those in the second half.

"You have got to work a lot harder when you are down to 14 men. You don't want to let your team-mates down.

"It shouldn't take us to be down to 14 men to spark up like that, but there is something about this team when we are put under pressure or down to 14 men that we really lift as a team.

"I think it's just wanting to work hard for your mate next to you, and I was really pleased with the way we played with 14 men, and the way we controlled the game at the end."