New Zealand, Fiji, Samoa and England all topped their groups on day one at the USA Sevens in Las Vegas, which also produced fine performances for USA, Japan and Guyana.
The Japanese beat the defending champions Argentina 7-0 early on and Guyana leaked a late try against France but still scored a fine 12-12 draw to underline Sevens' global appeal looking ahead to the 2016 Olympic Games.
Hosts USA lost by only two points to last weekend's Cup winners Fiji and finished the day with victory over North American rivals Canada to send the generous crowd of over 16,000 home happy.
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Samoan flyer Mikaele Pesamino grabbed the headlines by becoming the first player for over four years to score five tries in a single 14-minute match, against Chile. Pesamino also scored a fine hat trick against Scotland to stand well clear at the top of the try scorers list with eight.
Cup quarter finals
New Zealand v South Africa
Fiji v Australia
Samoa v Wales
England v Kenya
Vegas Play of the day: Pesamino five tries up
Pool A
New Zealand captain DJ Forbes led his side to a tight win against Australia at the end of the day, his the winning try in the 12-7 win to top the pool.
Both sides had opened up with convincing wins against France and Guyana to seal their places in the Cup quarter finals. Tim Mikkelson and his captain Forbes top scored for the kiwis with three tries apiece, while Brackin Karauria-Henry grabbed a hat trick for the Aussies against France to top score for them.
Guyana produced a brilliant display against the French, going ahead 12-5 before finally being pegged back to draw 12-12.
Pool B
World Series champions South Africa played some of their best rugby Sevens of the season against Fiji and came deperately close, just failing to capitalise on their possession in the face of some ferocious Fijian defence, which helped the islanders to hold on to their slender 12-5 lead in the pool decider.
Early on in the day, hosts USA came close to causing a huge upset against the Fijians. The Eagles led 5-0 at the break but the Fijians stormed back in the second half to edge it 14-12. Fiji followed that win with an improved display to beat Canada 26-12, while South Africa opened with convincing wins against Canada and gutsy USA to seal their place in the last eight of the Cup.
The Eagles most delighted the home crowd, though, getting the better of staunch rivals Canada in their final match to gain a more favourable Bowl quarter final draw.
Pool C
Mikaele Pesamino was in awesome try-scoring form as Samoa opened up with two strong wins against Scotland and Chile. Pesamino registered a hat trick against the Scots and then touched down five times in the win against Chile, before the Samoans rounded off an impressive day with victory against Kenya.
The record for the most tries scored in a single day of World Series action remains 10, by Fijian Vilimoni Delasau in Punta del Este in July 2000.
Kenya also started with two victories, first against the Chileans and then 17-0 against the Scots in front of a massive travelling African support.
Pool D
While Japan, Wales and Argentina took points from each other, England's opening two wins against the Japanese and the Welsh guaranteed them top place in the pool. The English drew 12-12 with Argentina in the final match of the day, but the game had little bearing on the pools, Wales finishing in second place to reach the Cup quarter finals.
Japan caused the first upset of the tournament by beating defending USA Sevens champions Argentina 7-0, their first win in Sevens against the Pumas in eight matches.
England fought from behind to beat Wales in the other opening match and then beat off a brave Japanese challenge to win 24-5, having been held to 5-5 at the break. Wales also scored a strong win against Japan.
Vegas welcome for the teams
So far this season New Zealand and Fiji have been the two teams to beat. The kiwis won the first two tournaments of the World Series in Dubai and George before Christmas to open up a lead and then in Wellington last weekend Fiji hit back to take their first title of the season and close the gap to just four points on the men in black at the top of the table.
IRB Sevens World Series: How it works
There are eight tournaments in the IRB Sevens World Series. Three have already been played - in Dubai, South Africa and New Zealand - and this is the fourth. Following the Las Vegas event the teams will rest and then travel to Adelaide and Hong Kong in March and finally London and Edinburgh in May.
Teams take a certain number of World Series points from each event, as follows:
| Trophy | Placing | Series points
| |
| Cup | Winner (1)
Runner Up (1) Semi Final (2) Quarter Final (4) | 24 points
20 points 16 points | |
| Plate | Winner (1)
Runner Up (1) Semi Final (2) | 12 points
8 points 6 points | |
| Bowl | Winner (1) | 4 points
| |
| Shield | Winner | 0 points
|