Defending champions Alinghi beat Team New Zealand by 30 seconds in the fourth race of the best-of-nine series to level the America's Cup at 2-2.
Alinghi established an early lead after a fiercely contested opening, and Ernesto Bertarelli's crew did enough to hold on for victory.
With light winds making for good racing conditions, the teams were level on the first leg before Alinghi edged ahead.
The Kiwis launched a protest after the race over the way the Swiss team raise and lower their mainsail although Alinghi crew members said there was nothing unusual about their rig.
