While the IRB hopes the hosts will be included, they will wait to see if the Brazilians can meet certain performance criteria by 2015.

It will be a similar system for the women's game, though there could potentially be more teams directly qualifying from the series than in the regions, according to Egan. "After the World Cup in June we'll have a better picture of the competitiveness of the women's game vis a vis each of the regions."

The IRB is confident its process will see the "universality of the sport represented" at the Games, while making sure the best teams take to the pitch in Rio.

"We will have the best teams there," assures Egan. "We've sat down with the IOC and they're very happy with [our selection process]."

But it means Hong Kong - whose chances of finishing in the top four or leading a World Cup repecharge tournament are slim - must remain the top team in Asia. And for the women, they have three years to get there.

"We can believe we can be the Asian champions, but a lot of other countries are coming up the ranks," said Hong Kong Rugby Football Union chairman Trevor Gregory.

"We had 18 countries participating in the Asia series last year. With all these teams improving, we cannot get comfortable."

Meanwhile, it will be a tougher challenge for the women. "China is targeting a women's gold medal - clearly - but our girls have got to keep improving and we are definitely targeting top three in any event," Gregory said.

While the fairness of the selection system is "unchallengeable", important details are still to be finalised, he said. "What Mark and I couldn't conclude today - and what needs to be concluded as soon as possible - is how a regional qualifier qualifies."

Gregory's preference is the Asia qualifier comes out of the winner of the Asia series. "We want to see the team that goes to the Olympics has had the chance to qualify over a period, rather than a one-off tournament - where someone might get injured or get a red card."

"But if we go down that route, we are going to have to face the fact our players are going to have a HKSAR passport," said Gregory, referring to the requirement that players must either be Hong Kong born or a passport holder, "and that will be a challenge."

The alternative would be a one-off tournament under IRB rules (which only requiring three years of residency). But where such a tournament is held, and in what format, may make an important difference.

"In one game, you could lose your chance to go to the Olympics. And out of 28 countries in Asia, who hosts that game would be an incredibly interesting debate."

While such a format holds more unknowns, it would get Hong Kong over the passport stumbling block - at least until they get to the Games themselves. In the meantime, the IRB is conscious it needs to build more competition for sevens to allow teams like Hong Kong to further develop against top international sides and has suggested a second world series may be in the works.

"We probably need a second tier series to run alongside the world series, or underneath it… because if you're not in the world series, where are you going to get your competition?" Egan asked.

"The challenge for us is to create competition for our unions to participate in. If we do that, it will drive the investment from NOCs and sponsors within the countries themselves."

But don't expect any extra funding, warns the IRB. "It's up to the unions to find their own funding," Egan said.