Cunha, who won the 25-kilometer race titles in 2015 and 2017, took her fifth gold medal and 11th overall at the world championships. She also won the 25-kilometer event in Shanghai in 2011, giving her four over the marathon distance.
Cunha finished in 5 hours, 8 minutes, 3 seconds, 8.60 seconds ahead of second-place finisher Finnia Wunram of Germany. Lara Grangeon of France claimed the bronze, 18.20 seconds behind Cunha. The race was held in rainy conditions, heavy at times, and the safety kayaks often had difficulty staying close to the swimmers.
"At the start of the race I wondered whether the event would last the entire 25 kilometers due to the rainy weather conditions and the problem with visibility," Cunha said. "I had my doubts and then considered that maybe we would only swim past three hours and then the race would be called off.
"So I wanted to be sure if that happened, I was leading at the time. But later I had no thoughts about the race being suspended. I was feeling really confident." In the men's race, Axel Reymond dueled with Russian Kirill Belyaev over the final meters before the Frenchman lunged ahead for a three-tenths of a second victory.
Reymond finished the men's race in a time of 4:51.06.20 while Belyaev clocked 4:51.06.50. Alessio Occhipinti of Italy earned the bronze medal, 3.30 seconds behind Reymond. Another Italian, Simon Ruffini, was fourth, 8.70 seconds behind. Australian Kai Edwards took fifth, 11 seconds behind Reymond.
The top Americans in the men's race were David Heron in 14th place, 4 minutes, 5.60 seconds behind the winner, and Brennan Gravley, who finished in 15th, 6:11.30 behind. American Erica Sullivan was fifth in the women's race, 3 minutes, 20.20 seconds behind Cunha, while teammate Katy Campbell finished in ninth place, 3:56.60 behind the winner.
Only two of the 24 starters failed the complete the men's race, while five of 21 women did not finish their race. The 25-kilometer races ended the seven-event open water program at the worlds. Only two open-water events will be held at the Tokyo Olympics next year — the men's and women's 10-kilometer races — and the top 10 finishes here qualified for those events.
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