Sir Ben Ainslie's team earned a spot in the Qualifying Series with two races to spare
Winds were again very light – racing was cancelled on Wednesday because of them – but just above the lower limit and the fleet struggled to lift the hulls on their foils.
But after a defeat to series favourites Emirates Team New Zealand in the second race of the day, Ainslie's crew pulled off a masterstroke midway through the last which left the French trailing in their wake.
France, Japan and Iain Percy's Artemis are now left to battle it out for the final two places in the semi-finals, which begin on Sunday.
Land Rover BAR aren't in action tomorrow but Ainslie insists they won't be resting on their laurels.
“We have to keep working on the boat," Ainslie said.
Land Rover BAR aren't in action tomorrow
"We are through now to the playoffs and we’ll see who we face there.
"Tomorrow we’re not scheduled to race but we will be out there working on techniques and trying to improve across the wind range.”
And Ainslie went on to admit the New Zealand defeat was probably the first time he had ever voluntarily retired from a race.
“We clearly had some issues controlling that daggerboard and we knew we had a big race coming up against France and decided to give our guys a chance to fix the issue, which they did brilliantly as always,” Ainslie added.
“Clearly our performance wasn’t good enough in those conditions. It was a tough day. We struggled in the light wind trying to get up on our foils, particularly downwind.”
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