Fiji's Rio Olympic rugby sevens gold medal-winning coach Ben Ryan said Saturday he hopes Tokyo will embrace the spirit of the sport when it hosts the Olympics in 2020.

Talking with Kyodo News at the Fiji Coral Coast Sevens at Lawaqa Park in Sigatoka, Ryan said the scale and nature of the event should ensure a carnival-like atmosphere at Ajinomoto Stadium.

"The fast-pace, the propensity for upsets and the relative ease of understanding the game make it the perfect Olympic sport," said Ryan, who led Fiji to their first Olympic medal of any kind. "You get a really nice mix of styles. It's a family carnival atmosphere. The athletes really are world-class and it's very physical."

"The Olympics are such a mix of countries that you could get a crowd that is a little bit different (from the normal, reserved rugby crowds in Japan). The Rio crowd was exactly that," he said.

"There were tons of people from nations that had nothing to do with sevens but who had heard that sevens is good fun to go to. The equivalent of the coconut wireless, it will filter down and people will say 'We can get a ticket for this and it is supposed to be really amazing.'"

The 46-year-old Englishman, who had his face emblazoned on commemorative banknotes and coins in Fiji after Rio and who was awarded a plot of land in Serua Province for his efforts, said American basketball star Carmelo Anthony was one of the Olympians enthralled by sevens.

"He watched all the games and he said it was just like watching basketball players playing rugby when he was watching the Fijian boys," said Ryan, who did some work with the New York Knicks, Anthony's former team, after the games.

On the field, Ryan said while it would be difficult for Japan's men's team to replicate their fourth-place finish in Rio, they will have a significant hometown advantage.

"Teams always over-perform in their home Olympic Games. But they are going to have to get their prep right."

Currently not part of the World Sevens Series, Japan's biggest problem could be a lack of big-match practice. But Ryan said that could also work to the advantage of Damian Karauna's side, who qualify automatically for Tokyo as host.

"They might fly a bit under the radar as they will not have the pressure the top teams have and they don't have to qualify via the regional qualifiers. For the 11 other teams, things change dramatically.

"Last time around Spain only found out a month before they were heading to the Olympics. So the fact Japan know they are in the Olympics and know their timetable is a massive plus."

Ryan said he had been approached by Japan in the wake of the Rio Games with a view to leading them at Tokyo, but said at the time he did not think it appropriate going from Fiji to another team. But he did have some advice in terms of team selection.

"They need to get their planning better than everyone in the world and that's an easy thing to do."

"With the planning comes identifying players for the Olympics and there will have to be discussions with the Japan Rugby Football Union if they are going to allow their very best players to have a tilt at it. And if they are, they need to get a conditioning strategy behind it."

And despite some saying the crossover from 15s to sevens is too difficult, particularly with the Olympics coming less than a year after the Rugby World Cup, Ryan said that was not the case.

"Some coaches say it takes six months or a season to turn someone around. I don't believe that. If you get your conditioning right I think you can turn someone around in eight weeks, less maybe. I really think you can."

And as to whether the future could see Ryan eventually working in Japan?

"I don't think our schedules match at the moment. But you never know what will happen in the future and you never shut the door. We'll see what happens."