Britain's INEOS Britannia and Italy's Luna Rossa Prada Pirelli yacht ended the first day of racing in the final of the Louis Vuitton Cup tied, with one win each on Thursday.

The Cup, held in Barcelona, will determine which team faces titleholders Emirates New Zealand in the America's Cup Match Race final in October. The first yacht to secure seven race victories will advance.

Luna Rossa claimed victory in the first regatta, which took place in consistent wind conditions. Meanwhile, INEOS Britannia secured the win in the second leg, which was held under more challenging, gusty winds.

"The conditions were very challenging and very tiring, but we worked well, and this will be a battle to the end," said Luna Rossa skipper Jimmy Spithill. "They (INEOS) pressured hard in the second race, the yacht handled well, and we are sure it's going to be a long duel."

INEOS captain Ben Ainslie explained that he had urged his crew to be "more aggressive" in the second race following their initial defeat.

"We sailed better in the second regatta, we made the boat sail better, although the Italians always remained close," Ainslie said. "We didn't get a good start, and the conditions were very different from the semifinals."