Amidst the colour and carnival atmosphere of the Gold Coast international rugby sevens tournament, Australia are making a serious bid to win the event.

Australia haven't won a sevens tournament on home soil in a decade but they go into Sunday's finals day in a strong position to end that drought after winning all three of their pool matches on Saturday.

Top spot in Pool B and a quarter-final against Kenya was the prize for a thrilling 15-14 win over defending champions Fiji in the last match of the day.

Jordan Tuapou was the hero for Australia, diving over in the corner late in the second half to seal the stirring three tries to two victory.

Fiji scored in either half through Joji Baleviani Raqamate but a double to Allan Fa'alava'au and Tuapou's brave effort secured Australia's first sevens win over Fiji since May 2011.

"To finally finish it off was a great plus," Tuapou told AAP.

"It was a team effort but obviously in the end I ended up getting the ball just to put it down.

"It's a great confidence boost for us ... it doesn't matter about the first day, it's what you put on the paddock the second day that counts."

Only Luke Morahan's knee injury less than a minute into the tournament dampened the party atmosphere among the 12,558 fans at Robina Stadium dressed in all sorts of fancy-dress outfits.

Morahan limped off the field with medial ligament damage to his knee in Australia's opening match against Tonga, a game the hosts won impressively 31-14 to get their sevens world series campaign off to a good start.

"It's not looking too good, I don't think he'll be back out tomorrow unfortunately," captain Ed Jenkins told reporters.

In fact, the injury is all but certain to end Morahan's hopes of going on the Wallabies end of season tour of Europe, after the Queensland Reds back rushed back from international duty in Argentina to be part of the sevens team.

His teammates didn't seem to miss the flier however, sealing a quarter-final berth with an emphatic 22-0 thrashing of Scotland in their second game in Morahan's absence before their epic win over the Fijians.

Jenkins has labelled South Africa as the competition favourites after they completed a trio of wins in Pool A by upsetting the fancied New Zealand 31-21 in the penultimate match.

South Africa now face France in the quarter-finals with the winner of that match to meet Pool C winners Samoa or Fiji in the semis.

Australia will face either Argentina or their great rivals New Zealand if they overcome Kenya.

Sunday's action begins at 10.30am AEST with Australia's quarter-final to be played at 1.04pm AEST.