CNN  — 

If Japan was to lift the Rugby World Cup on November 2 it would constitute one of the greatest shocks in sporting history.

The home nation is in the second tier of rugby playing nations, but landed a remarkable 19-12 win over world No.1 Ireland Saturday to add to an historic victory over mighty South Africa four years ago.

Combined with a 30-10 win over Russia in its opening game this year, one former World Cup winner senses an uplift in confidence from Japanese rugby fans.

“They feel they can win,” former Australian scrumhalf and captain George Gregan told CNN’s Alex Thomas in Tokyo.

Gregan, who is the Wallabies’ most capped player with 139 appearance, was integral to Australia’s 1999 World Cup triumph.

Back then, only a handful of nations realistically harbored hopes of winning the quadrennial tournament. Today, that list has grown. And according to Gregan, Japanese fans believe the Brave Blossoms should be on the list of potential champions.

“The game is getting closer and closer,” added Gregan.

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Japanese players celebrate during their game against Ireland in Shizuoka on September 28.

Most competitive World Cup

The reduction in the gap between tier one nations – those competing in the elite competitions of Europe’s Six Nations and the southern hemisphere’s Rugby Championship – and the tier two nations has made this year’s showpiece the most competitive yet.

Only four teams have won the World Cup since its inception in 1987 – New Zealand, Australia, South Africa, and England – with the All Blacks having won back-to-back titles in 2011 and 2015.

“The first team to go back to back was New Zealand, no one else has done it,” Gregan said. “It shows how hard it is to do it. To get in a final and then win it. It’s not easy.”

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George Gregan played 139 Tests for Australia.

One of the favorites to go all the way this time is England. The men in white had a disastrous outing on their own patch four years ago where they were unceremoniously knocked out at the group stage. But under the tutelage of Eddie Jones, the 2003 champion has transformed into a formidable unit.

“Eddie is the best coach I’ve ever had,” said Gregan of his countryman, who was the Japan coach four years ago, and was also an assistant coach in South Africa’s victorious 2007 set up after taking Australia to the 2003 final.

“He sometimes breaks you down to build you up. He is so supportive of his playing group. He can coach everywhere. He’s coached in Japan, he’s coached South Africans, he’s coached Aussies. If you spoke to the majority of people who were coached by Eddie, he made them better players.”

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CHOFU, JAPAN - SEPTEMBER 20: A Japan fan poses for a photo outside the stadium prior to the Rugby World Cup 2019 Group A game between Japan and Russia at the Tokyo Stadium on September 20, 2019 in Chofu, Tokyo, Japan. (Photo by Cameron Spencer/Getty Images)
Rugby superfans cycle from London to Tokyo
03:06 - Source: CNN

Love for Japan

But Jones is not the only Australian with roots in the Land of the Rising Sun.

Gregan spent three years with Suntory Sungoliath from 2008 to 2011 and spoke enthusiastically of the country and its welcome for visiting rugby fans.

“I love Japan,” he said. “I’ve liked how comfortable people feel in the cities. It’s so organized and the local people are so welcoming.”

Japan next take on Samoa Saturday before a crucial clash against Scotland on October 13. Win both, and Japan would defy the odds and top its group. From there, who knows how far the Brave Blossoms could go?