Day one of the Cathay Pacific/HSBC Hong Kong Sevens produced competitive action across the board with the 28 teams either looking to take the famous Hong Kong title and earn Sevens World Series points, or keep alive their hopes of winning core team status for 2013-14 series.

In the main tournament, the top sides in the world, including Wales, Argentina, New Zealand, Kenya, Samoa, Portugal, Canada and Fiji, all scored opening wins.

The Pumas were ruthless in seeing off United States Sevens champion South Africa 21-0, while Samoa also looked a genuine title contender in beating England 28-7.

Defending champion Fiji started with a 36-0 win over host Hong Kong, while SWS leader New Zealand came from behind to beat France 33-12. Portugal scored a last-gasp win against Scotland.

Zimbabwe and Russia impressed in series qualifying. While the top 16 - the current 15 core teams and Asian champion Hong Kong - compete in the main competition, 12 regional qualifiers are looking to keep alive their hopes of gaining core team status on the 2013-14 SWS.

To do that they need to finish in the top four of the 12-team competition and book a place in the promotion/relegation playoff finale in London in May.

This year's Rugby World Cup Sevens host, Russia, and the Cheetahs of Zimbabwe both scored impressive opening wins in the same pool. Georgia and Japan eked out tougher victories against Hong Kong debutants Jamaica and Brazil, while Uruguay and Tonga also scored opening wins, the Tongans battling back from behind to edge Tunisia by two points.

With 28 nations and regions competing, the Hong Kong event has also attracted more live broadcast takers than ever before with 23 airing live coverage to 144 countries, a new record for a single round of the series.

After five rounds of the 2012-13 HSBC SWS there have been five different winners.

Fiji won the opener in Australia, Samoa claimed the cup in Dubai, New Zealand triumphed in South Africa, England won in New Zealand and South Africa took the USA Sevens in Las Vegas.

As the only side to have reached all five Cup quarterfinal rounds, New Zealand is first in the standings on 96 points, followed by South Africa (73), Samoa (71), Fiji (66), France (59) and Kenya (57).