Four qualified for quarters after opening encounters in Las Vegas

New Zealand, Kenya, South Africa and Australia have all booked their spots in the quarter-finals at the HSBC USA Sevens after an enthralling opening day of action at the Sam Boyd Stadium.
HSBC USA SEVENS DAY ONE AS IT HAPPENED >>
Four spots are still up for grabs with the all-important and decisive third round of pool matches taking place on day two before the quarter-finals in Las Vegas, with more record crowds expected after a new day one attendance record of 18,441 turned out.
RE:LIVE! He's done it, 150 tries for @humphkj, also the 1,500th for @kenyasevens! Celebrating with @nfl style #Dabhttps://t.co/fD1GB0wMri
— World Rugby Sevens (@WorldRugby7s) March 5, 2016
In Pool A, back-to-back champions from Wellington and Sydney New Zealand picked up where they left off in round five of the HSBC World Rugby Sevens Series, scoring 80 points and conceding just one try in wins over Russia and Portugal, the same sides that tasted defeat to Benjamin Ayimba's Kenya.
Humphrey Kayange scored his 150th and Kenya's 1,500th sevens try in their win over Russia while Collins Injera scored three times on day one to move within three tries of Ben Gollings and second place in the all-time leading try-scorers list behind Santiago Gomez Cora.
LAS VEGAS FIXTURES AND RESULTS >>
South Africa also won both of their matches on day one with Bryan Habana returning to rugby sevens after a 12-year absence to score one of the tries of the day as the Blitzboks opened up with a 33-7 win over Canada before Seabelo Senatla scored a hat-trick in their 36-7 win over Wales, taking his tally for the day to five and 30 for the season.
Canada bounced back from their defeat to Neil Powell's side to draw 26-26 with the hosts USA with both sides aiming to take the second qualification spot from Pool D.
WHO'S FASTER THAN YOU? 11.16 seconds for an actual length of the field try for @speedstick11! #USA7s @usainbolthttps://t.co/cTyv8t5lIo
— World Rugby Sevens (@WorldRugby7s) March 5, 2016
The hosts won their opening match 19-12 against Wales before the enthralling draw with North American rivals and next week's hosts Canada. Having led 26-7 thanks to two superb tries from Perry Baker, Conor Trainor, Nathan Hirayama and Phil Mack, playing in his 50th tournament, drew the scores level to leave it all to play for in Pool D.
.@BryanHabana scores his first sevens try for the @Blitzboks! Only took 12 years #roadtorio pic.twitter.com/n4jsyc3F3p
— World Rugby Sevens (@WorldRugby7s) March 5, 2016
Elsewhere Pool C is wide open after defending Las Vegas champions and current series leaders Fiji lost to Samoa in their opening match of the day, their first defeat in a pool match since the 2014 London Sevens, before beating France 42-12.
Samoa had the chance to qualify for the Cup with a victory over Argentina but were beaten 25-12 with Bautista Ezcurra scoring twice in the win. Los Pumas' win was their second of the day having earlier beaten France but must wait until day two to confirm qualification for the last eight with a match against Ben Ryan's Fiji.
Australia were the only other side to win both of their matches on day one, beating Scotland and Japan in Pool B to secure qualification to the last eight.
England left it late to snatch a 19-19 draw with Japan who had led 19-5, Jack Wilson and Phil Burgess scoring the tries to secure the draw before they lost to Scotland 24-14 in the last match of day one.
RE:LIVE! @manusamoa end impressive @fijirugby pool stage run, dating back to London 2014, with this match-winnerhttps://t.co/GPXnkmY9DN
— World Rugby Sevens (@WorldRugby7s) March 5, 2016