Ainslie, who picked up first and second place finishes to move ahead of Sweden's Daniel Birgmark after four races, was one of three British boats to move into pole position.

Dave Evans and Ed Powys earned two wins out of three to go top of the 49er standings, while Sophie Weguelin and Sophie Ainsworth hold the overall lead in the 470 women's event.

Lucy Macgregor, Annie Lush and Kate Macgregor moved into the quarter-finals of the women's match racing event with six wins out of eight, while Iain Percy and Andrew Simpson climbed to third overall in their Star keelboat.

Olympic champions Percy and Simpson are back in competitive action for the first time since the World Championships in Perth, where their challenge was ended by a back injury suffered by Percy.

Percy said: "We've been a little bit haphazard, but over the next few months we've got quite a lot of competitions, and the thing for us is to use those regattas to get race-sharp for the Olympics."