While the Japanese rugby team has captivated a second-straight Rugby World Cup with its giant killing on the pitch, for many local fans of the sport, the tournament's main attraction is a side with a somewhat more illustrious pedigree.

The Brave Blossoms' 19-12 win over heavyweight Ireland over the weekend may have given sales of the hosts' red-and-white jersey a big boost, but around Japan's World Cup venues, Japanese fans sporting the iconic black shirt of three-time champion New Zealand are an ever-present sight.

Ahead of New Zealand's Pool B match with Canada at Oita Stadium on Wednesday, scores of Japanese supporters of the All Blacks converged on the city on the southwestern main island of Kyushu.

Longtime fan Tota Serino traveled from Fukuoka to watch the game. A rugby player in his younger years, he said he was drawn to New Zealand not just because of its dominance on the field, but for its exciting, up-tempo style.

"When I started playing and watching rugby, I was immediately attracted to them," Serino said.

New Zealand's influence runs deep in Japanese rugby. Japan head coach Jamie Joseph is a former All Black, while captain Michael Leitch and veteran forward Luke Thompson — now playing in his fourth World Cup for Japan — were both born in New Zealand.

Several Kiwi players and coaches have also been instrumental in raising the level of Japan's professional Top League over the years.

All Blacks great Dan Carter was a huge draw for the competition in 2018, pulling in big crowds and winning league MVP in his first season with Kobe Kobelco Steelers.

Nozomu Ibusuki, a fan of Top League side Toshiba Brave Lupus, fondly recalls watching former All Blacks center Scott McLeod play for the western Tokyo-based club.

"He was a really good player who made a big contribution to the team," said Ibusuki, who counts two-time World Cup-winning captain Richie McCaw as his favorite former All Black.

Oita resident Shoichiro Shuto, 29, said he had been an All Blacks fan since taking up rugby as an 8-year-old.

With the team based in Oita Prefecture in the lead-up to the match, Shuto said he had attended the training sessions that were open to the public.

"When you hear the name "the All Blacks," right away you think of the best rugby team in the world," Shuto said.

Among the black-clad fans at Oita Stadium were also a number of newer converts.

Sakiko Yoshida said she had enjoyed rugby since her son took up the sport in high school, but had become captivated by New Zealand while watching the broadcast of its thrilling 23-13 win over South Africa in Yokohama on the first weekend of the tournament.

"Watching them perform the "haka," I felt this team was something special," said Yoshida, adding she has become a big fan of fullback Beauden Barrett.