The defending champion sailed smart from the start today and overcame the challengers from New Zealand in the fourth race to even the best-of-nine America's Cup series at 2-2.

"We need to win five, that's all that matters," said Alinghi owner Ernesto Bertarelli, who was aboard SUI-100 as a crew member.

The Swiss yacht lost the third race at the finish line in shifting winds yesterday. This time, Alinghi kept Emirates Team New Zealand close and dictated the race for a 30-second win.

"Even though we had a very hard day ... it was easier, not much easier but a bit easier to control this regatta," Bertarelli said.

Alinghi skipper Brad Butterworth put in a superb performance after the Swiss started off on the right for the first time in the series and never gave up the starboard advantage. The Kiwis attempted to engage the Swiss, but the SUI-100 yacht answered every move and the defending champion led around every marker.

The victory means the race to win the Auld Mug, the oldest trophy in international sports, will be the closest since 1983, when Australia II came from behind on the final leg to win the series against Liberty and take the America's Cup away from the United States for the first time in its then 132-year history.

The fifth race is scheduled for Friday.

Team New Zealand helmsman Dean Barker came off the start on the left, gambling that wind conditions would prove favorable. But the Kiwis came out slightly behind when crashing waves added extra resistance in the soft but steady breeze.

Alinghi sailed high off the right to hold a slight edge, with Butterworth winning the initial leg to go around the first marker with a 20-second lead.

Barker responded with a "sambuka" — a maneuver that involves a 180-degree turn — that caught the Swiss off guard as they turned clumsily despite having spent the morning practicing.

Butterworth ignored a chance to split and maximize the SUI-100's speed since it cost the Swiss in the previous two flights.

The Kiwis lost more time when their flowing red spinnaker was tangled up into an hourglass shape as they attempted to engage the leaders only to lose valuable seconds.

After a slow rounding at the second marker left Alinghi with a 34-second lead, helmsman Ed Baird stayed with Barker on the second upwind lap that was identical to the first — both teams sailing up to the left — except that the boats were separated by more than a half-mile.

Barker tacked back to avoid getting pushed out again and cut the deficit to 25 seconds.