It proved to be an action-packed opening day of the Sailing World Cup in Hyères ©World Sailing

Olympic champions Martine Grael and Kahena Kunze of Brazil enjoyed an ominous start to the Sailing World Cup in Hyères as they finished the opening day of racing at the summit of the women's 49erFX leaderboard.

The Brazilian duo have been the dominant forces in the classification having won the gold medal on home water at last year's Olympic Games in Rio de Janeiro and at the Sailing World Cup final in Miami in December.

Grael and Kunze recorded results of first, second and a discarded fourth to end on three points, one in front of Argentinian pair Victoria Travascio and Maria Branz, while Norway's Helene Naess and Marie Rønningen follow in third.

Panagiotis Mantis and Pavlos Kagialis, bronze medallists at Rio 2016, lead the way in the men's 470 class on six points having finished first and fifth in the two races.

Jordi Hernandez and Nicolas Rodriguez of Spain are second, one point adrift, with the Swedish team Carl-Fredrik Fock and Marcus Dackhammar third on nine.

Home sailors Moana Vaireaux and Manon Audinet were also in good form as they claimed results of a discarded fourth, first and second to surge to the summit of the Nacra 17 standings on three points.

Lin Ea Cenholt and Christian Peter Lubeck of Denmark, and defending champions Fernando Echavarri and Tara Pacheco of Spain, both have six points.

The conditions were excellent for sailors across all of the classes on day one ©World Sailing
The conditions were excellent for sailors across all of the classes on day one ©World Sailing

Belgium's Evi Van Acker, bronze medallist at London 2012, got the defence of her title off to the best possible start as she has an eight-point advantage over the rest of the laser radial fleet.

The Belgian was third in the opening race of the day and won the second to finish the day on four points, with Lithunian Viktorija Andrulyte her closest challenger with 12.

Hungary's Mária Érdi also remains in contention as she has 14 points.

Switzerland's Mateo Sanz Lanz proved to be the most consistent in the men's RS:X as he had a first-place result either side of a discarded fourth to end on just two points.

Italy's Mattia Camboni is second on four, with Israel's Shahar Zubari a point further back in third.

"As soon as you get clean wind you can get free and choose whichever side you want," said Lanz. 

"It's the one thing that makes a huge difference to where you finish.

"I'm happy as it was a tough day of pumping all the time in gusty conditions. 

"But I managed to start with clean wind and sailed fast."

The event continues tomorrow.