The first Rugby World Cup in Asia kicked off with host Japan securing the win it needed to get momentum rolling.

Now for the biggest showdown of the group stage, with the New Zealand All Blacks facing South Africa's Springboks in Yokohama on Saturday.

The All Blacks, aiming for an unprecedented third consecutive World Cup title, have never lost a match in the pool stage of the tournament. But they're facing a daunting opener against South Africa, which won the southern hemisphere's Rugby Championship this season for the first time in a decade. The most recent game between the traditional heavyweights of the sport resulted in a 16-16 draw in July, and they're 2-2 in previous Rugby World Cup meetings.

New Zealand All Blacks players  train during their captain's run prior to the Rugby World Cup in Tokyo, Friday, Sept. 20, 2019. New Zealand will meet with South Africa on Saturday. (AP PhotoKoji Sasahara)

New Zealand All Blacks players train during their captain's run prior to the Rugby World Cup in Tokyo, Friday, Sept. 20, 2019. New Zealand will meet with South Africa on Saturday. (AP PhotoKoji Sasahara)

Two-time champion Australia gets its Pool D campaign started against Fiji in Sapporo, in the north of Japan, and France and Argentina meet in Pool C.

More AP Rugby World Cup: https://www.apnews.com/RugbyWorldCup and https://twitter.com/AP_Sports

Japan players bow to the crowd as they celebrate following their 30-10 win over Russia during the Rugby World Cup Pool A game at Tokyo Stadium in Tokyo, Japan, Friday, Sept. 20, 2019. (AP PhotoJae Hong)

Japan players bow to the crowd as they celebrate following their 30-10 win over Russia during the Rugby World Cup Pool A game at Tokyo Stadium in Tokyo, Japan, Friday, Sept. 20, 2019. (AP PhotoJae Hong)

South Africa’s Pieter-Steph du Toit carries a ball during the team's training for the Rugby World Cup in Yokohama, near Tokyo, Friday, Sept. 20, 2019. South Africa will play against New Zealand in Pool B on Saturday, Sept. 21. (Kyodo News via AP)

South Africa’s Pieter-Steph du Toit carries a ball during the team's training for the Rugby World Cup in Yokohama, near Tokyo, Friday, Sept. 20, 2019. South Africa will play against New Zealand in Pool B on Saturday, Sept. 21. (Kyodo News via AP)