Rainsley said she was inspired by an earlier silver medal for partner and fellow endurance athlete, Tom Bishop, at an Ironman 70.3 race in Geelong, Australia.

Zaferes’ fellow American, Kirsten Kasper, claimed bronze, and promptly declared herself “in the mix” for Olympic qualification.

There was a Spanish one-two in the men’s event, with Garcia leading home Antonio Serrat Seoane. Kenji Nener, the Japanese reigning Asian Games champion and world No 14, finished third.

Zaferes won individual bronze at the Tokyo Olympics, and became a mum the following year. However, the 34-year-old has ruled out continuing until the 2028 Los Angeles Games, heightening the need to reach Paris this summer.

She completed the Central Harbourfront course in 59 minutes, 53 seconds, which left her nine seconds adrift of Rainsley, but seven seconds in front of teammate Kasper.

Zaferes said her display felt like “redemption”, after she withdrew during the running leg of the American Triathlon Championships a fortnight ago, when husband and coach, Tommy, said his wife “melted in the heat”.

Memories of that episode in Miami played on Zaferes’ mind, “not in the best way”, as she raced under a scorching Hong Kong sky.

“In [Miami] my legs started tingling, it freaked me out, and I think I disengaged,” Zaferes said. “Today, when my legs went tingly, I put the thought to one side. Having such a tough race … really prepared me to hurt this week. It was pretty upsetting, but it helped me here.”

Zaferes is vying for one of two remaining spots in the US Olympic team, with former Ironman world champion Taylor Knibb already qualified.

“I would love to be in Paris, and think I am capable, but this feels like a bonus round,” Zaferes said. “Do not hold me to anything I say, right now, but I will not carry on [after Paris].

“We want another child, and I have really enjoyed my career. I am not going to say I will retire, but I am not sure what I want to do.”

Rainsley, ranked 177 in the world, after an injury-hit 2023, downplayed her own Olympic hopes, because “the British women are so strong”.

The 26-year-old was racing for only the fifth time since the 2022 Commonwealth Games.

“I have done a lot of training with my partner [Bishop], which has increased my strength,” Rainsley said. “We have trained in Thailand and Australia, and tried different things with our programmes. His podium this morning gave me the confidence I could do the same.”

Men’s champion Gonzalez, the world No 39, finished in 53 minutes, 17 seconds, to become the day’s second maiden World Cup winner.

Gonzalez, 25, was effusive about a “tough course”, because “some in world triathlon are getting easier, and this was fun”.

He added: “The pressure is high for every race in Olympic year, but I try not to think about it too much.”

Serrat, No 19 in the world, came home five seconds after his compatriot. Nener, the final member of a breakaway triumvirate who laid waste to the field, was another two seconds behind, his legs buckling as he slumped hard against an advertising board after crossing the line.

“I am absolutely spent, but I have to learn to keep pushing, and that is what I did,” Nener said. “It is hard to say whether I can transfer my [Asian] form to world level, but … it is good to get some momentum. Today was always going to be a challenge, and the races will get harder from here.”