As New Zealand and Britain set out to sea for their latest America's Cup head-to-head, both crews will be scanning the surface for wind shifts to gain an edge in the tricky Mediterranean conditions off Barcelona.

Emirates Team New Zealand has taken another step toward retaining the America’s Cup after making it 4-0 over INEOS Britannia.

Britain won a second race in their head-to-head America's Cup final against New Zealand on Wednesday, reducing the holders' lead to 4-2 in the first-to-seven-points series in testing sea conditions off Barcelona,