Australia faces a must-win final pool game against Fiji this evening to stay alive in the London Rugby Sevens tournament.
Fiji hopes to play spoiler, knowing a win would seal a place in the quarter finals giving them an unassailable lead in the World Series.
Should Fiji lose to Australia, in-form South Africa are close enough to leap frog the Pacific Islanders into first place.
Australia beat Wales 22-10 earlier on Saturday to begin their Twickenham campaign, but a last-minute loss to England left them third in Pool B with just one game to play.
The Aussies led 7-5 at halftime thanks to a late Sam Figg try, which cancelled out Dan Norton's opener.
Marcus Watson scored late on to send England top of the pool with a game against cellar dwellers Wales to come.
Fiji beat Wales 42-5 and will start as warm favourites against Australia.
Code hopper Jarryd Hayne is expected to feature against Australia, having played about 10 minutes in Fiji's first two pool games.