The top four seeds - Australia, New Zealand, Canada and Great Britain - will battle it out for the first Olympic sevens medals at the Deodoro Stadium on Monday.
HSBC World Rugby Women's Sevens Series champions Australia powered past Spain 24-0 to set up a last four showdown with Canada, who needed two late tries to beat France 15-5.
The other semi-final pits Great Britain and New Zealand against each other after they enjoyed contrasting wins over Fiji (26-7) and the USA (5-0) respectively.
Earlier in the day New Zealand and Great Britain had both ended the pool stages as the only sides with a perfect record, topping Pool B and C respectively, after top seeds Australia needed a last-minute conversion from Chloe Dalton to scrape a 12-12 draw with the USA in Pool A.
The semi-finals begin at 14:30 local time (-4 hrs BST) with Australia taking on Canada before Great Britain meet second seeds New Zealand. The day's play will get underway two hours earlier with the 11th place play-off between Colombia and Kenya, which will be followed by the battle between hosts Brazil and Japan for ninth and the fifth place semi-finals.
Australia had been given a scare in their final pool match by the USA, but it was normal service resumed for the HSBC World Rugby Women’s Sevens Series champions in the quarter-finals with Charlotte Caslick crossing twice to join team-mate Emma Tonegato on six tries at Rio 2016.
Ellia Green added a try on the hooter for a 24-0 victory to set up a semi-final with Canada, who beat France 15-5 in a much closer affair that was only decided in the final two minutes with tries from Bianca Farella and Ghislaine Landry which left Les Bleues ruing missed opportunities.
Fijiana's hopes of winning their country's first ever Olympic medal were ended by Team GB, who never looked back after Abbie Brown (main picture) scored from the kick-off in the third quarter-final. Brown added a second with Alice Richardson and Joanne Watmore also crossing the whitewash.
The last quarter-final was decided by a single try from Portia Woodman, who ended day two tied with Australian duo Tonegato and Caslick as the leading try scorers at Rio 2016. Woodman's try came on the stroke of half-time and New Zealand were able to hang on against a USA side who had been denied the scalp of Australia in the pool stages at the death.
NINTH PLACE SEMI-FINALS
Their medal hopes may have ended after missing out on the quarter-finals, but Brazil and Japan still have plenty to play for on Monday in the ninth place play-off as the winner will secure a place on the 2016-17 HSBC World Rugby Women’s Sevens Series as a core team.
Hosts Brazil proved too strong for their fellow South Americans Colombia to make it two wins from two on Sunday, Claudia Teles scoring two of their four tries in a 24-0 victory which had the crowd on their feet again.
Japan also won by the same scoreline against Kenya. Marie Yamaguchi perfectly read the Kenyan play to intercept and power away for the first of two first-half tries for her as the Sakura Sevens picked up their first win of the Olympic Games.
SESSION ONE REVIEW
Fiji had earlier made certain of a place in the quarter-finals with a 36-0 defeat of Colombia, but they only knew their final position in the pool after Chloe Dalton's last-minute conversion secured Australia a 12-12 draw with the USA. With plenty of offloading traditionally associated with Fijian sevens rugby, Raijieli Daveua grabbed Fijiana's first two tries in a comfortable victory over their lesser experienced South American opponents.
Australia, like New Zealand, had looked invincible on day one but also found life hard-going against a side who took the match to them, competing well at the breakdown and forcing the top seeds into errors. Tonegato gave Australia the lead and it took an fantastic try-saving tackle by Caslick on Victoria Folayan to deny the USA a breakaway try. They did score twice through Jessica Javelet after the break, but Tonegato's try meant the USA were denied what would have been a well-deserved win.
New Zealand began in the same vein as the opening day with tries from Kelly Brazier, Huriana Manuel and Woodman putting them in control, but a try from Camille Grassineau on the stroke of half-time gave France hope. A much-improved performance from France in the second half put New Zealand under pressure for the first time in the competition and errors followed before Kayla McAlister made certain of the win and top spot in Pool B.
Spain knew a win was essential if they were to realise their target of a top eight finish in Rio and Barbara Pla set them on the road to victory, only for Kenya to score a great team try through Doreen Nziwa to tie the scores at half-time. Two tries by Marina Bravo, though, saw Spain to a 19-10 win which was enough to claim a best third-placed spot.
Great Britain caused an upset by emphatically beating a Canadian side who looked a shadow of their day one selves to top Pool C. Team GB pressurised Canada into making error after error and punished them with tries from Richardson, Amy Wilson-Hardy and a quick-fire double from captain Emily Scarratt securing a 22-0 win.
Hosts Brazil had failed to score a try on the opening day but it was fitting that their long-serving captain Paula Ishibashi crossed for that maiden score against Japan and the home crowd were in raptures as two tries from hometown girl Beatriz Futuro Muhlbauer, either side of one by Amanda Araujo, gave them a 26-10 victory. The margin wasn't enough to secure a quarter-final place as one of the best two third-placed sides, missing out on points difference to Spain.
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