Ainslie is a four-time Finn class world champion

Ainslie, competing in his first Finn race in 12 months, came first in the opening race and finished just behind winner Jan-Pieter Postma in the second.

Britain's Sarah Ayton, Sarah Webb and Pippa Wilson lead the rest of the field in the Yngling class.

And Paul Goodison also made an impressive start in the laser class.

Ainslie said that weather conditions in the Yellow Sea had made life difficult for all the sailors.

"It was hard work out there - we had between six and 12 knots and some pretty big waves to contend with," said Ainslie.

"We also had a few small wind shifts and the tide was quite tricky, so I tried to be a bit conservative - it was definitely a head out of the boat kind of day."

Ayton, Webb and Wilson are just one point ahead of the American team of Sally Barkow, Carrie Howe and Debbie Capozzi after two races.

Goodison placed third and fourth in his two races to take an early lead, while Nick Rogers and Joe Glanfield came fourth and fifth in their two races to put them ahead in the men's double-handed class.