Nippon's loss was the first in six races since it switched to its second boat for the start of the third round-robin, and came as light winds in Auckland's Hauraki Gulf again distorted winning margins.

Thursday's results dropped the Japanese team from second to fourth in the standings and strengthened AmericaOne's hold on the lead. The top six boats advance to the next round.

AmericaOne leads the competition with 90 points, followed by America True (83), Prada (82), Nippon (74.5) and Stars and Stripes (63.5).

Nippon skipper Peter Gilmour won the start over AmericaOne counterpart Paul Cayard and the two boats were closely matched during a tacking duel on the first beat.

But AmericaOne pulled away after rounding the first mark. The Americans were able to find some breeze in the light and shifty conditions, while Nippon appeared almost becalmed.

At one stage during the race, AmericaOne caught up to Stars and Stripes, which started its race against the French team 10 minutes before the AmericaOne-Nippon clash. America True, which started 10 minutes behind, caught up to Nippon.

AmericaOne's biggest lead of the race was almost 12 minutes before Nippon made up some of the gap. The winning margin was 9:08.

America True gained an easy win and moved into second place by sailing the course alone after its scheduled rival, the Swiss team Fast 2000, withdrew from the series earlier this week.

Italy's Prada, which held the lead until two days ago, defeated the Spanish challenge by 5:29 to move into third.

Le Defi Francais defeated Stars and Stripes by 4:03 and remained in ninth place. Stars and Stripes is still in fifth.

Abracadabra defeated Young Australia by 1:21.