New Zealand made sure of top spot in Pool C at the Rugby World Cup thanks to a rousing second-half performance in their final group game against Tonga on Friday.

The All Blacks led by just 11 at half time and were extremely close to conceding a couple of tries before the Tongans ran out of steam in the final half-hour, with New Zealand's quality telling as they ran out 47-9 winners.

Fly-half Dan Carter is the all-time leading scorer in Test rugby and now has 1,552 points to his name after successfully converting six of the seven Kiwi tries in Newcastle.

Sports Mole caught up with the 33-year-old after the match to get his thoughts on what was, for the most part, a closely-fought contest at St James' Park.

Were you quite surprised by how Tonga matched you in the first half and at the start of the second?

"No, not at all. We know a lot of their players from internationals and Super Rugby. They're extremely physical players, so we were expecting that kind of physicality.

"We just had to be patient with the ball. We thought that if we did that to put them under a bit of pressure and make them defend for long periods then the game would open up and we would be able to score some tries, and that's the way it went."

Is there a sense of relief at all that you were able to see them off towards the end, or is it just about topping the group?

"Well one of the most important things for us is that we finished in first place in the group and gave ourselves a chance of playoff rugby. We've done that, so we're really pleased with where we're at.

"We realise that there's still room for improvement, but we'll take a lot of confidence out of that second half. Saying that, we've got no guaranteed games after this quarter-final so we can view it as a final and we have to step up and improve."

Is it a concern at all that you didn't really get going until after the 50th minute?

"I guess it's just the way the game goes. I think the gap between [the higher and lower tier] teams has closed a lot. Blowing teams away right from the start is sort of unseen these days, but we were confident if we just held on to the ball and were patient that we would score.

"It's all part of the plan of making sure that we finish strongly. There are areas that we'll have to address and we'll review the game to make sure that we start a lot better [in the quarter-final]."

Reigning champions New Zealand, who are looking to become the first nation to win back-to-back World Cups, will face the loser of Sunday's Pool D showdown between France and Ireland in the last eight.