The Flying Fijians, the HSBC World Rugby Sevens Series champions for the last two years, battled past Japan 20-5 in the first semi-final with Josua Tuisova among their try-scorers.
The second semi-final was even tighter, Great Britain emerging the 7-5 victors over Commonwealth Games champions South Africa with Tom Mitchell’s conversion the difference between the sides.
The bronze medal match kicks off at 18:30 local time (-4 hrs BST) with the gold medal battle to follow at 19:00. The final session of six days of Olympic rugby sevens gets underway an hour earlier with the play-off for fifth and seven places.
Fiji made the perfect start when Vatemo Ravouvou broke round the side of the Japanese defence for the opening try, but he turned villain with a yellow card and Japan made the most of their man advantage with Teruya Goto powering over to tie the scores at 5-5.
An acrobatic dive from powerhouse Josua Tuisova ensured Fiji went into half-time ahead at 10-5 and they increased that advantage with tries by Semi Kunatani and Jerry Tuwai, the latter with Lomano Lemeki in the sin-bin for Japan.
Japan, the surprise package of the competition, battled to the finish but couldn’t deny Fiji a 20-5 win.
South Africa had lost their speedster Seabelo Senatla to injury, but in his absence Rosko Specman was showing his own pace by bursting through the Great Britain defence at will early on. It was a great flick of the floor by Phil Snyman that gave Kyle Brown a run-in for the only try of the first half.
The Blitzboks’ lead lasted less than minute as Team GB worked the ball wide and Dan Norton stepped inside Dylan Sage to race clear and under the posts, captain Mitchell crucially adding the conversion for a 7-5 lead.
Neither side were able to find another score so it was Great Britain celebrating at the final whistle.
FIFTH PLACE SEMI-FINALS
New Zealand have never lost four matches in a single tournament on the series and they avoided doing so on the Olympic stage only after second-half tries from brothers Akira and Rieko Ioane and Regan Ware’s second of the match secured a 24-19 win over France.
Ware had opened the scoring only for two tries by Stephen Parez to give Les Bleus a 12-5 half-time lead. The second half belonged to New Zealand, though, with France only able to manage a consolation try with time up through Sacha Valleau, a sevens gold medallist at the Youth Olympic Games in Nanjing two years ago.
The second semi-final was only decided in added time after Argentina staged a remarkable comeback from 21-0 down to beat Australia 26-21, Matias Moroni scoring the winning try just as he had to snatch victory against the USA on day one.
A brace of tries from Tom Cusack and another from Con Foley had put Australia in the driving seat, but Argentina captain Gaston Revol scored a try with time up in the first to give his side hope. Revol scored again early in the second and Moroni cut the deficit to two before his match-winning try.
NINTH PLACE PLAY-OFF
The USA had lost one of their speedsters Perry Baker to a calf injury after day two, but that just gave Carlin Isles more time on the pitch and the former sprinter responded with two run-ins from long-range.
Spain had scored the opening try through Pablo Fontes, a late injury replacement for Pablo Feijoo for the final day, but Isles and Danny Barrett put the Eagles Sevens ahead. Spain pulled it back to 12-12 through Angel Lopez’s try but further scores for Maka Unufe and Isles wrapped up the 24-12 victory.
11TH PLACE PLAY-OFF
Kenya had hopes of a medal when they arrived in Rio, not playing off for 11th place play-off but they ensured they finished their Olympic campaign with a first victory, Billy Odhiambo scoring a hat-trick in a 24-0 defeat of hosts Brazil.
Willy Ambaka was the other try scorer for Kenya as the hosts appeared to run out of steam. Brazil did think they had scored a try at the death through captain Lucas Duque, but the pass from his brother Moises was forward to the dismay of the home fans in the crowd.