The vuvuzelas have gone quiet, the national flags have been put away, and the cable sports networks are back to talking about baseball. But the World Cup in South Africa has left its mark on soccer in the United States, and, if pattern holds, it will help the sport continue to grow in this country.

Even though the American team had long since left the tournament, more than 24 million fans watched the championship match, between Spain and the Netherlands, on ABC and Univision, a figure more than the average viewership for last year’s World Series games between the Yankees and the Phillies.

Midfielder Landon Donovan became a household name thanks to his on-field exploits for the United States. Americans bought more tickets to World Cup games than fans from any country other than South Africa, and more than half a million fans are expected to see Europe’s best teams play in the United States this summer, including the 44,213 who saw Manchester United beat the host Philadelphia Union, 1-0, on Wednesday at Lincoln Financial Field.

Major League Soccer also got a boost from Thierry Henry, the French striker who signed with the Red Bulls this month. Henry made his debut Thursday, scoring his team’s goal in a 2-1 exhibition loss to Tottenham Hotspur in Harrison, N.J. He is the latest in a string of high-priced, aging superstars to join M.L.S., a list that includes Cuauhtémoc Blanco, Freddie Ljungberg and David Beckham.