LONDON (Reuters) - The world's fastest-growing sport. That status is claimed by many, but rugby union has a genuine shot at the title on the back of a record-breaking Rugby World Cup.
As the tournament approaches its climax, having smashed attendance and TV audience records despite host nation England's early exit, the sport aims to build on growth from Asia to Europe and the Americas.
Data collected by governing body World Rugby shows that player numbers climbed to more than 8 million last year from 5.48 million in 2012.
"We're going into new countries all the time, huge new programmes in countries like Mexico and India, and we're going into Mongolia and Asia," World Rugby's head of competitions and performance, Mark Egan, told Reuters.
"It's all about getting in there on the ground, going into schools, educating parents about our sport, the strong values our sport has. It's a very powerful message."
The emergence of Italian rugby offers a vivid illustration of the game making its mark outside established strongholds.
For decades rugby in Italy was very much a niche sport, but since it joined Europe's Six Nations championship in 2000 the number of registered players and coaches has climbed to 110,000 from 25,000, the Italian Rugby Federation (FIR) says.
Aided by the increased media exposure, FIR revenue has increased tenfold to 40 million euros-plus ($45 million) since 2000, making it one of Italy's wealthiest sporting federations.
Riccardo Sironi, trainer at OverBugLine Rugby in the northeastern town of Codroipo, said hardly anyone in Italy had heard of rugby when he first played in 1974. But now even little Codroipo has teams from under-6s to under-14s, with 100 children signed up.
"Demand from families keeps on growing, because rugby is not just a sport but a life school," he said.
Women's rugby is also taking off. The number of women FIR cardholders has risen to 7,200 from 600 in 2000 and Italy finished third in this year's Women's Six Nations, with victories over France, Scotland and Wales.
Japan, meanwhile, is making huge strides, though participation has fluctuated over the past 20 years.
With only one victory from seven previous World Cups, Japan pulled off the biggest upset in the tournament's history by beating South Africa in their opening game and were desperately unlucky not to progress beyond the pool stage.
The Brave Blossoms' exploits drew record TV audiences in Japan, reaching 25 million for the game against Samoa, which augurs well for when they host the 2019 tournament.
"Maybe there were 30 million people in Japan watching this game. That's the whole of the Australian population, plus the kangaroos, and New Zealand and all the sheep," Japan's Aussie coach Eddie Jones said after their closing win against the United States.
"Now out of that 30 million people there are kids that want to be the new Michael Leitch (the Japan captain). It's a fantastic opportunity for Japan."
The success of the tournament is seen by World Rugby as the springboard to further growth.
"The game was on a upward spiral anyway, but I do think the Rugby World Cup is giving us huge exposure," Egan said.
"Japan beating South Africa and the competitiveness of the Tier Two countries is opening us up to a lot of new markets ... we have seen some good growth in Central America, El Salvador, Guatemala, also in Ecuador.
"I think we have three million in Germany who are tuning in to the World Cup."
Overall figures for Europe show an increase of about 13 percent since 2012 to 3.45 million players. Of the smaller rugby nations, Germany, Russia, the Netherlands, Poland and Malta have all at least doubled playing numbers.
World Rugby is investing 350 million pounds across 120 national unions between 2009 and 2016, with nearly half going outside the top-tier nations.
But while the overall picture is of rugby on the rise, drill below the headline numbers and a more nuanced trend emerges.
Though World Rugby's data shows total playing numbers have risen 46 percent since 2012, the age breakdown indicates that the main driver is pre-teen rugby, which jumped by 88 percent, with teen participation up 29 percent.
The number of adult players, however, has dipped by 3 percent over the same period.
It is a phenomenon familiar to many at grassroots level.
Maidenhead RFC, an amateur club competing just below the English national leagues, has a flourishing youth section, but senior playing membership that once supported eight teams has dwindled and only three sides now run out every Saturday.
"Our youth rugby is very strong, with good numbers of players and qualified coaches. We have 400-plus kids from under-6s to under-16s, plus 40 to 50 colts," club chairman Stephen Bough says of a youth section that counts England's James Haskell among its impressive alumni.
"But like many clubs, we struggle with senior numbers," he added, citing the pressures of work and family.
World Rugby is aware of the divergence but expects the sheer weight in numbers of children taking up the game to boost adult participation in the years ahead.
"That is what makes the grassroots, mass-participation programme at youth level so important," World Rugby media manager James Fitzgerald said.
There is also the potential for the sport to follow a different route entirely.
Player numbers in the lucrative U.S. market have exploded since 2012, rising by nearly 350 percent to almost 1.5 million. But it is the 'how', rather than the 'how much', that could be most significant.
There are signs that USA Rugby could devote less time and money to 15s and focus on the Sevens format -- a less complex, broadcaster-friendly game that has gained inclusion at next summer's Olympic Games in Rio de Janeiro.
Las Vegas is already part of the World Sevens series, San Francisco has been awarded the 2018 Sevens World Cup and, tellingly, the USA won the last World Sevens tournament at Twickenham in May and are a medal prospect in Rio.
But America is by no means the only country showing appetite for the 15-a-side game's upstart cousin.
"Rugby needs the Olympic movement to be global," said Carlos Barbieri, president of Rugby South America, noting that Brazil is investing heavily in the game, particularly Sevens.
"It's a question of idiosyncrasy, the beautiful game, a fast game that you can even play on the beach."
While World Cup semi-finalists Argentina clearly lead the pack in South America, participation numbers in Brazil have soared to about 420,000 from only 13,000 in 2012, with female players accounting for a third of the total.
"The Brazilian women are learning fast, quicker than the men, and playing at a level that allows them to have a team on the World Sevens circuit," Barbieri said.
The rugby purists need not panic about a Sevens revolution quite yet, however.
"It's a brand of rugby that has taken off in the States in a big way," said former England scrumhalf Nigel Melville, now chief executive of USA Rugby. "That doesn't mean 15s isn't being played ... (Sevens) is just another brand.
"It's global, its an Olympic sport, its something special and helps us all grow the game."
(Additional reporting by Rex Gowar and Himanshu Ojha in London, Julian Linden in Singapore, Valentina Consiglio in Rome; Editing by Angus MacSwan)