There may have been broken hearts and shattered dreams across the United States on Tuesday, but MLS promoters say unprecedented enthusiasm for the national team is evidence that Major League Soccer has come of age.

In the MLS offices in New York, all eyes were on Brazil, where Team USA weathered a 90-minute assault by a powerful Belgium to lose 2-1 in extra time at the World Cup, sending the Americans home.

On the same day, league officials celebrated in Orlando, Florida, where attacking midfielder Kaka, who in 2002 helped Brazil win a fifth World Cup, signed a contract with expansion MLS club Orlando City to become one of the biggest names in the league.

Both events add to the growing evidence that soccer has finally secured more than just a foothold in the United States, and that the anti-soccer fatalism that followed the collapse of the North American Soccer League in 1984 has withered.

In Brazil, coach Jurgen Klinsmann's USA side impressively managed to go through from the so-called "Group of Death" featuring Germany, Portugal and Ghana, a feat many observers described as all but impossible.

"We proved to the world we are a soccer nation!" MLS Commissioner Don Garber said on Twitter minutes after the USA-Belgium clash.

Millions of Americans have been glued to the action in Brazil: an impressive 14 million watched Germany beat USA last Thursday.

Because it was mid-week, the game also drew a record 1.7 million online viewers -- even more than American football's Super Bowl, traditionally the biggest sporting event in the United States.

With interest reaching fever pitch, corporate sponsors have lined up behind the team.

What thrills Garber even more is that Klinsmann stacked his starting lineups with an average of six MLS players for each World Cup game.

"We need to be a league of choice for the top players in the world, and that starts with being the league of choice for top American players," Garber said.

US stars Michael Bradley and Clint Dempsey recently returned to play on American soil after successful European club ventures.

MLS has already earned a strong foreign contingent, including French superstar Thierry Henry, who joined the New York Red Bulls in 2010.

Spain's all-time leading goalscorer David Villa and former Real Madrid and Milan star Kaka have signed respectively with New York City FC and Orlando, two expansion teams set for their debuts in 2015.

MLS, created in 1996 on the heels of the successful US hosting of the World Cup, is no longer seen as the poor cousin to top sports leagues like NFL football, Major League Baseball and NBA basketball.

With 18,608 spectators on average per match, MLS has the third-highest per-game attendance of any US league, ahead of the NBA and NHL hockey.

If Australian international Tim Cahill, who now plays for New York after many successful years in the English Premier League, is to be believed, the MLS is no league of last resort for aging stars.

"I think the best thing, more than anything, was my decision to come to the MLS," said the veteran, who scored one of the goals of the tournament before the "Socceroos" departed the World Cup at the group stage.

It is not only international talent gaining interest in soccer's new El Dorado.

Investors like Austrian energy drink Red Bull, Indonesian businessman Erick Thohir (DC United), a member of the Abu Dhabi royal family (New York City FC), and David Beckham, who is launching the new MLS team in Miami, are all involved.

The US market has stirred interest from English, Italian and Spanish clubs including Manchester United, AS Roma and Real Madrid, all of which are due to tour America before the new season.

"Soccer has had a number of false starts here" when Americans "weren't quite ready," Bill Sutton, founding director of the Sport and Entertainment Management program at the University of South Florida, told Sports Business.

"They're more ready for it now than I've ever seen."