Twickenham - Michael Leitch paid tribute to former coach Eddie Jones on Friday for changing Japan's rugby culture, on the eve of a Twickenham reunion with the now England boss.
Japan, next year's World Cup hosts, will be looking for another landmark victory on English soil.
Jones guided Japan to a stunning 34-32 win against South Africa at the 2015 World Cup in England, the biggest upset in the history of rugby union.
Japan captain Leitch, also the skipper three years ago in Brighton, was happy to acknowledge veteran Australian coach Jones' contribution to that shock success over the Springboks.
"I have been in Japan for 14 years, so I have a lot of experience there and one thing I always noticed was beating a bigger opponent always seemed impossible because they have longer arms and longer legs - that was always the excuse," the New Zealand-born back-row forward told reporters at Twickenham on Friday.
"Eddie came along and changed how we thought about that, he changed the culture," said Leitch, who moved to Japan as a teenager.
"When kids in Japan look at the national team, they see a team that is willing to win and beat top teams.
"Japanese rugby culture now is all about going out there to win."
Jones, in the build-up to just the second full international between England and Japan, advised his former side to "go to the temple and pray", such was the determination of his current team after their agonising 16-15 loss to three-time world champions New Zealand at Twickenham last weekend.
"You have got to love Eddie!," said Leitch when asked about the remarks of Jones, Australia's coach when they lost the 2003 World Cup final to England.
"But those comments, I can't really say anything."
Saturday's match will be the first time the 30-year-old Leitch has played at the 82 000 capacity Twickenham.
"It is the home of rugby, being out there today (Friday), I felt so lucky to play for Japan, captain Japan and showcase Japanese rugby at Twickenham.
"Tomorrow will be an extremely proud moment," he added.
Japan prop Koo Ji-won said just taking to the Twickenham turf had been a daunting experience.
"It's the first time that I have been to Twickenham. It's such a huge stadium and just thinking about tomorrow night makes me a little bit nervous," admitted Koo.
"But the ground condition is perfect and I think it's the best pitch you can ever have."
Few pundits give Japan a hope of victory on Saturday, no more than they did prior to their defeat of South Africa.
But Koo said the team's self-belief had also been bolstered by a 23-23 draw with France in Paris last year.
"We do talk about that (beating South Africa) but we also talk about playing against the French last year," explained the tighthead. "We drew but that gave us a lot of confidence, so we would like to beat England tomorrow and draw attention to Japanese rugby."