After three years of preparation, it all came down to a spectacular come-from-behind of a few hundred yards. By that stretch of deep blue water and a margin of 41 seconds, the lovely white-hulled Australia II, whose mystery keel had captured even landlubbers' imaginations, sliced across the finish line on Rhode Island Sound ahead of Liberty, the America's Cup defender, thereby ending the longest winning streak in sports history. After 132 years on U.S. soil, if one can refer to a glass case in the elitist New York Yacht Club that way, the "auld mug" would be going abroad for the first time. Yet the man most responsible for that wasn't even on board Australia II when the sleek upstart crossed the line. Ben Lexcen, its gruff 47-year-old designer, was watching from a tender when his revolutionary boat won the race and, most salts now agree, changed ocean racing forever.

When Australia II was hoisted out of the water five hours after that deciding seventh encounter last September, non-Aussies got their first look at the invention Lexcen had until then kept shrouded in plastic when it wasn't in the ocean. They saw a squat keel that seemed to be upside down and had "winglets" flaring off the bottom. Looking back on the whole heated summer, during which competitors of several nations fought him on legal ground as well as on the sea, and even sent divers to photograph his keel underwater, Lexcen now says he never doubted the technical supremacy of his creation.

Having been proved on water, Lexcen's winged keel was legally sanctioned, once and for all, last month by the International Yacht Racing Union in London, a decision that sent designers around the world scurrying to their drawing tables. "All the shackles are off, and we're heading into the most interesting period in the history of yacht design," Lexcen says with relish. "It's unlikely that I designed the best boat of its type on the first try."

As inaugurator of the new era, Lexcen is now home in Sydney, charged by syndicate head Alan Bond with cooking up a new 12-meter boat to defend the Cup in January 1987 on the Indian Ocean off Fremantle. Lexcen often works on his assignment for up to three days without sleep.

In the wake of victory, he is forgiving of the often questionable tactics of his foes. He lays the Americans' legal antics to "the terrible responsibility of defending this bloody relic, like an icon." Won't he himself feel that way in three years? "I don't consider the Cup a religious icon," Lexcen scoffs, smiling. "It's just a bloody beautiful old thing." Right you are, old digger.