Leading contender Thomas Coville crashed his trimaran into a freighter to become the highest profile victim of a storm that forced at least six competitors out in the opening hours of the Route du Rhum transatlantic yacht race.
Former Olympic pole vault champion Jean Galfione was also among the victims to crash out of the race from St Malo to Guadeloupe.
"I have the impression that I hit a truck with a motorbike," the still-shocked Coville said as he returned to the French port of Roscoff on Monday with his vessel, the 31-metre Sodeb'O Ultim.
The 46-year-old Frenchman, a renowned round-the-world sailor who came third in the last Route du Rhum in 2010, said he was moving at about 40 knots (75 kilometers an hour) when he hit the freighter on Sunday night.
"The moment that I hit was the worst moment of my life," added Coville.
Ninety-one yachts left St Malo on Sunday, but at least six had abandoned by Monday morning and four more were heading to port for emergency repairs.
Galfione, the 1996 pole vault gold medalist, had only been in the race for six hours when his Serenis Consulting hit an unlit buoy. Francois Angoulvant had to be rescued from his boat by a helicopter after losing his rudder.
Early race leader Loic Peyron, on Banque Populaire VII, said the seas were "Dante-esque".
Source: AFP