New Zealand were unforgiving as they punished South Africa errors to get their Rugby World Cup title defence under way with a thrilling 23-13 victory in the blockbuster Pool B clash in Yokohama.

Rugby Championship winners South Africa had been tipped as the leading contenders to dethrone New Zealand in Japan and they piled the pressure on the All Blacks in the early stages.

However, they only had three points from Handre Pollard to show for their efforts before sloppiness set in during a six-minute blitz that included tries from George Bridge and Scott Barrett.

Pieter-Steph du Toit crossed and Pollard scored a fine drop-goal as the Springboks regained a foothold in the second half, but the All Blacks were able to retain their record of having never lost a group stage match.

Pollard split the posts in the second minute after Bridge was pinged for not releasing the ball, and the Springboks maintained their commanding start.

He then hit the upright from the tee after Faf de Klerk intelligently won another penalty, but the scrum-half's stray pass was pounced on by Richie Mo'unga and Makazole Mapimpi's illegal attempt to win it back led to the fly-half restoring parity.

The champions had clicked into gear and Mo'unga's cross-field kick enabled Sevu Reece to charge down the right, setting a move in motion that ended with Beauden Barrett darting through a gap and offloading for Bridge to score his eighth try in six Tests.

New Zealand punished another mistake when Pollard dropped a high ball and Anton Lienert-Brown skipped in off the right before sending Scott Barrett under the posts, while Mo'unga missed a chance to make it 20-3 at the break from the left touchline.

Du Toit took advantage of a defensive lapse from the All Blacks to run straight in from a ruck in the 48th minute and Pollard reduced the arrears to four points with a stunning drop-goal from 40 yards out.

Mo'unga slotted through another penalty and the boot of Beauden Barrett helped keep the Springboks at bay as New Zealand extended their winning run in World Cups to 15 matches.

De Klerk opens the door

South Africa were in complete control until De Klerk's sloppy pass was set upon by Mo'unga, and it proved to be the turning point. New Zealand added 17 points in the next five minutes to underline their status as favourites for the trophy, with Rassie Erasmus likely to have concerns over the fitness of Trevor Nyakane and Cheslin Kolbe after late injuries.

Barrett at full-back pays off

Hansen's decision to play Mo'unga at fly-half and Beauden Barrett at 15 paid dividends, with both playing important roles as playmakers as the All Blacks tore South Africa apart in the first half. The latter was then granted the chance to play the last 10 minutes in his favoured position.

Key Opta Facts

- South Africa have lost the opening match of their last two Rugby World Cup campaigns - they had won their opening game in each of their previous five tournaments.
- New Zealand have never lost a World Cup pool stage match, winning each of their 29 such fixtures; the All Blacks have also won 15 in a row overall in the tournament, extending their record run.
- South Africa missed 35 tackles in this game, their second highest tally in a Rugby World Cup match after their 45 missed tackles against the All Blacks during their clash at the 2003 World Cup.
- Beauden Barrett made 17 carries in this game, the most by a New Zealand player in a World Cup match since Luke McAlister, Rodney So'oialo and Richie McCaw all made exactly 17 against France in 2007.
- Pollard has slotted three drop goals in the World Cup since the beginning of 2015, more than anyone else (Dan Carter and Nicolas Sanchez - two each); just five players have more overall at the tournament.
- No side has ever lost a match during an edition of the World Cup and gone on to lift the Webb Ellis Cup, each of the previous eight tournaments seeing the eventual champion record a 100 per cent win rate in the pool stage before going on to lift the trophy.

What's next?

The Springboks return to action against neighbours Namibia in Toyota next Saturday, while the All Blacks must wait until October 2 to take on Canada in Oita.