"This tournament has been a great start to our Olympic qualifying campaign. We might have lost all our games but we were up against some of the best teams in the world, all of them regulars on the World Series," said Rees, the Hong Kong Rugby Football Union's head of technical development and performance.

"We have earned a lot of respect from the core teams, all of whom were made to fight for every point for every minute against Hong Kong. We are now in a good place to move forward and try to qualify for the Rio Olympics," Rees said.

Rees, who accompanied the 12-man squad to Tokyo, declared the first steps in the six-month build-up to the vital Asian Olympic qualifying tournament in Hong Kong in November as an unqualified success.

Hong Kong were invited to participate with the core teams in the seventh leg of the World Series, and ended the first day losing to England (33-0), Fiji (35-14) and Wales (31-5) in pool competition.

They then went down fighting to Samoa (21-0) in the Bowl quarter-finals, before losing 19-17 to Portugal in the semi-finals of the Shield.

"The emphasis this weekend was on players needing to stay in the 'now' in every minute of each game, playing each phase with huge fight, work rate and determination and this has been evident in all our performances this weekend," Rees said.

"The guys did Hong Kong proud and it was disappointing not to have picked up a win. We kept improving with each game, even the restarts," Rees said.

"We won all our kick-offs against a taller and bigger Samoa, as well as taking two of their balls. We showed that if you pressurise and fight for everything, the opposition game will break down under the constant pressure."

Hong Kong will host the 12-team men's Asian Olympic qualifiers at Hong Kong Stadium in November and can expect a tough challenge from Japan for the solitary automatic Asian berth for the 2016 Rio Olympics.

In the Japan Sevens Cup final on Sunday, England upset series leaders South Africa 21-14. At one stage, England led 21-7 before South Africa notched a late converted try.

The Blitzboks edged Fiji 7-5 in the semi-finals while England posted a 14-5 win over Canada to advance to the final. New Zealand were bundled out in the quarter-finals by Canada.

The top four teams at the end of the current Sevens World Series season gain automatic entry to the Rio Olympics, with two of the nine legs remaining - Scotland and England in May.

South Africa lead the standings on 129 points. Fiji have 125 points, New Zealand 120 and England 100.