(FORTUNE Magazine) – It's the biggest event in sports, more important to some members of the international community than diplomacy or trade. Little wonder then that soccer's faithful feared disaster when rights to stage the 1994 World Cup were won by a backwater of the sport -- the United States. Surprise: Americans have gobbled up nearly all 1.2 million World Cup tickets available here, overwhelming forecasts. ''It tells us there's a tremendous pent-up demand for the product,'' says Hank Steinbrecher, executive director of the U.S. Soccer Federation. Overseas sales begin this fall. The 52-game series is expected to create $4 billion in Cup-related revenues. More American kids play soccer than baseball or football, but converting youthful enthusiasm into paying customers has been a toe stubber for the sport. However, last month's U.S. Cup, a six-game, four-team trial run, averaged 48,000 fans per match. More important, it made millions. Says Steinbrecher: ''The sport is really starting to generate revenue, income, and exposure. That's what you have to do to be a sport in America.'' Soccer apparel has even become trendy. Eurosport, a mail-order catalogue of the stuff started by 27-year-old Mike Moylan as a teenager, now goes to more than four million customers in the U.S.; sales, now $20 million, have doubled in each of the past three years. Umbro, once a little-known uniform maker in England, is a hot logo. ''You see it all over the college campuses,'' says Andy Logan, Eurosport's 28-year-old CFO. Umbro is now owned by Stone Manufacturing Co. of Greenville, South Carolina. Worldwide sales, now more than $300 million, are growing at a rate of 70% a year. Results on the field are improving too. In the U.S. Cup, the Yanks lost 4-3 to world champion Germany but thumped England 2-0, creating a national crisis there. ''We can't get any lower,'' screamed the English tabloid Today, acknowledging that another U.S. ''product'' is now globally competitive.