The first race started in a relatively benign 11 to 12 knots, but the breeze suddenly shifted 30 or 40 degrees to the left with less than a minute to the start gun, playing nicely into the hands of Besson and Riou who had been fighting hard for position at the left-hand of the start line. 

The French duo put the hammer down out of the line and tacked on to the layline to establish a lead that they never relinquished. 

Switzerland’s Matías Bühler and Nathalie Brugger came second ahead of Spanish pairing Iker Martinez and Julia Rita.

The results remain in doubt, however, after some teams submitted protest forms claiming that most of the fleet failed to go around the spacer mark at the top of the second windward leg.

It is claimed the race committee had moved the windward mark to take account of the big wind shift, and that most of the sailors failed to see the small spacer mark that had been situated nearby and assumed that there was no space mark at all.

Also having to contend with the difficult conditions in Florida was the men’s 49er fleet as Denmark’s Jonas Warrer and Anders Thomsen made a winning start in the discipline's World Championships.

Warrer, the Beijing 2008 Olympic champion, was dunked into the water on the downwind leg when a trapeze adjuster slipped out of its cleat, dropping the Danes a few places.

But having managed to regain composure, he and Thomsen made amends on the next windward leg before going on to cross the line in first place.

Reigning world champions Peter Burling and Blair Tuke also charged through to win their half of the qualifying fleet, putting New Zealand in an early tie with Denmark for first.

Rounding out the tie for third is Great Britain’s John Pink and Stuart Bithell, and France’s Julien d’Ortoli and Noé Delpech.

With the breeze whistling up to over 20 knots, and the waves becoming ever more treacherous, the race committee was forced to abandon any further racing for the day.

Weather is expected to be more moderate tomorrow with manageable breezes.

Many countries will be sending their best performing crews at the World Championships to the Rio Olympics this year.