Fiji, who had lost narrowly to Wales in their opening game, are now in line for a spot in the knockout stages, leaving Australia needing to beat the Welsh and setting up the prospect of a nail-biting tussle to decide the top two places in the pool.
Simione Kuruvoli kicked four first-half penalties to give Fiji, better known for their running rugby, a 12-8 lead at the break and a Wallaby defensive error allowed Josua Tuisova to score a try early in the second half.
Fiji opened up a 22-8 lead with 12 minutes left before Suli Vunivalu reduced the deficit with a try for Australia, for whom Mark Nawaqanitawase also scored a first-half try.
(FRANCE 24 with Reuters and AFP)
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Mark Nawaqanitawase