Tokyo Olympics 2021: Stephanie Gilmore crashes out of Tokyo Olympics after making 'frustrating', pivotal decision

Australian seven-time world surfing champion Steph Gilmore was surprisingly knocked out in Round Three of the women's event at the Tokyo Olympics.

Gilmore crashed out of the competition after being defeating by South African underdog Bianca Buitendag, scoring 10.00 to 13.93 at Tsurigasaki Surfing Beach.

The Aussie was upset after failing to capitalise on her chances in poor surf conditions, with a pivotal decision not to take the heat's highest scoring wave, proving most costly. That allowed Buitendag to catch it instead and score a 7.10, despite Gilmore holding priority.

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"I looked at that wave and I was like, it doesn't look that good, so I let her have it and she turned it into a seven, so that was the most frustrating thing to me," Gilmore told reporters.

"Like, man, I should have just taken that wave."

Despite being 33 years old, Gilmore did not rule out contending for the Paris Games in 2024, with the shock Tokyo Olympics loss sure to provide added motivation.

"That's just the nature of surfing, sometimes the waves are there, sometimes the waves are not," Gilmore said.

"I still get to call myself an Olympian, which is pretty rad," she added.

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For Buitendag it was one of the biggest results of her career.

"I had nothing to lose, absolutely no pressure," she said.

"I am the underdog coming in at 17th seed for this event. I had nothing to lose and it's a really comfortable spot to be in.

"It was very hard [to pick the right waves], but I knew I was up against Steph, who is the best women's surfer in the world so I knew I had to be on the best waves, otherwise I stood no chance."

Australia still has Sally Fitzgibbons in the women's draw, as well as Julian Wilson and Owen Wright in the men's competition on Monday.