Anderson, the world champion in Barcelona two years ago, clocked a time of 58min 48.4sec to finish 1.4 seconds ahead of Greece’s Kalliopi Araouzou in second, while Germany’s Finnia Wunram took bronze.

The 23-year-old found herself in fifth position at the halfway stage, 3.6 seconds behind The Netherlands’ Sharon Van Rouwendaal, who led for nearly the entire race.

Anderson sprinted to the front of the pack in the final 300 metres and held on to become only the third woman to win multiple gold medals in the event after Russia’s Larissa Ilchenko and Italy’s Viola Valli.

"The conditions were great today and I am really happy with my finish,” said Anderson, Olympic silver medallist in the 10km at London 2012.  

“I really just wanted to get on this course as a tune up for the 10km.

“I am confident that I am prepared for the 10km race next week.

“This victory means a lot.

“I take this process of qualification for the 2016 Olympics only one step at a time.

“Today's race is a stepping stone to the 10km where I hope to qualify for Rio.”

In the men’s event, Chad Ho won South Africa’s first gold medal in open water swimming, narrowly defeating Germany’s Rob Muffels with a time of 55:17.60.

Behind them and completing the podium was Italy’s Matteo Furlan.

"I'm over the moon, I honestly couldn't believe the result,” said Ho.

“Today’s race was brutal, the wind was something else, and I had to fight the wind just to get a nice line.

“It was a perfect start to my World Championships.”

Elsewhere, host nation Russia secured their first gold medal of the Championships thanks to Svetlana Romashina’s triumph in the women’s solo technical synchronised swimming competition.

A total of 95,2680 points saw Romashina finish ahead of Spain’s Ona Carbonell on 93.1284 and China’s Sun Wenyan on 91.5479.

In the diving competition, China won gold medals in both the mixed synchronised platform and women's 3m springboard synchronised events.

A total of 15 pairs competed in the mixed synchronised platform which was introduced on the competition programme for the first time.

Si Yajie, defending champion in the women's 10m platform, teamed up with fellow teenager Tai Xiaohu and led from start to finish to win with 350.88 points.

Canada's Meaghan Benfeito and Vincent Riendeau came second with 309.66, while Australia’s Domonic Bedggood and Melisa Wu took bronze with 308.22.

Olympic champion Wu Minxia won her eighth world title from as many World Championships with success in the women’s 3m springboard synchronised, alongside Shi Tingmao.

The action in Kazan is due to continue tomorrow with the Championships set to run until August 9.

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