The race formed a key part of the swimmer's preparations for the FINA World Championships, due to be held from July 24 to August 9 in Kazan.

Burnell enjoyed the perfect preparation for the marathon swim in the Russian city, by taking victory in Lake Balaton, a popular seaside resort in Hungary, after fast men’s race which saw the swimmers completing the four-lap course.

The Briton had formed part of the leading group after the opening two laps in Lake Balaton but broke free on the third lap after increasing the pace, as he looked for his second consecutive victory on the World Cup circuit having won in Cozeumel, Mexico, in May.

He secured the victory by extending his lead in the final lap of the race to touch first in 1 hour 41min 41.93sec, with the silver medallist Greece’s Spyridon Gianniotis finishing three seconds adrift.

Italy’s Simone Ruffini was able to deny home favourite Gergely Gyurta from taking the bronze medal as he finished in 1:41:46.35, while the Hungarian was a further second in arrears to finish fourth at his home World Cup event.

Brazil’s Ana Marcela Da Cunha took the women's title having finished as the runner-up last time out in Mexico, as she posted a time of 1:50:36.68 to win a closely fought race.

Éva Risztov of Hungary claimed silver in 1:50:37.69, while Britain's Olympic silver medallist Kerri-Anne Payne secured bronze having finished in 1:50:38.87.

The British athlete was just 0.5 second ahead of fourth place finisher Rachele Bruni of Italy.

Setubal in Portugual is due to host the sixth leg of the 10-event FINA World Cup on June 27.

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