Australian Nikki Van Dijk's win over Courtney Conlogue means Carissa Moore is on the verge of her third world surfing title.
Moore, from Hawaii, is into the quarter-finals at the Maui Pro.
The last event of the women's world tour finally started on Monday (AEDT) in solid surf after eight days of the holding period.
Australian Sally Fitzgibbons has also made the quarters after the opening day of competition, but only Moore or Conlogue can claim the world title.
Van Dijk beat Conlogue (USA) and Johanne Defay of France in their round-three heat.
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That put Conlogue into the sudden-death fourth round and if she loses there, Moore will be world champion again.
While Conlogue faltered in the third round, Moore dominated her first and third-round heats to reach the quarters.
If Moore loses her quarter-final, then Conlogue would have to win Maui to claim the world title.
If Moore lost in the next round and Conlogue finished runner-up, it would be a tie and they would have a surf-off to decide the world champion.
Conlogue would have to win Maui if Moore reaches the semis, while Moore claims the world title if she makes the final.
"(We) can't really affect each other in the world title race," Moore said.
"There's other factors and we won't be each others factors, so we just have to go out there and do our thing and surf our best."
Conlogue will go up against fellow Hawaiian Coco Ho in round four.
Tyler Wright is the other Australian left in the Maui Pro and she has a round-four heat against Hawaiian Malia Manuel.
