A San Francisco medical examiner has ruled that British sailor Andrew Simpson died from "blunt trauma with drowning".
The two-time Olympic medallist died in May this year while training for the America's Cup when the catamaran he was racing capsized in the bay.
The report, which ruled the 36-year-old's death as an accident, stated that his helmet showed signs of being crushed.
Organisers of the America's Cup went on to introduce 37 safety recommendations following the incident, including the introduction of breathing equipment for sailors and body armour.