Women’s professional soccer will return to the United States in 2013, as U.S. Soccer president Sunil Gulati announced last week the formation of a new league that will feature teams based in some of the nation’s biggest soccer hotbeds. The new league, the third attempt at forming a successful top-notch women’s soccer league in the U.S., will have eight teams based in Boston, Chicago, Kansas City, Western New York, New Jersey, Portland, Seattle, and Washington, D.C.

As I wrote in August, when the U.S. Women’s National Team was on its way to its second consecutive Olympic gold medal, making a women’s league successful won’t be easy. But the focus for U.S. Soccer president Sunil Gulati, who made a women’s league a priority when WPS folded, is now on sustainability, and that is already evident in the early formation of the new league.

U.S. Soccer has promised to pay the salaries of 24 players — three per team — who are on its full-time roster. The Canadian and Mexican soccer federations announced this week that they too will fund salaries of players who join the league from their national teams. The backing of those three foundations will give the new league a financial crutch WPS and WUSA never had, a significant break for a league that will need help attaining financial viability.

Regardless of the challenges the league faces, this is a positive step for the women’s game. The absence of a professional league made it impossible for the game to take advantage of the enthusiasm brought on by the 2011 World Cup and 2012 Olympics, particularly in the United States, where players like Abby Wambach, Hope Solo, and Alex Morgan blossomed into full-fledged stars outside the small world of women’s soccer fans. It also left those players with no top-level professional league to return to, making it harder both for the U.S. to sustain its dominance of the women’s game and harder for the game to grow.

That growth is important. There are now more than 337,000 girls playing soccer on 10,500 teams at the high school level, and another 700 teams play collegiate soccer. The growth of the women’s game internationally has followed the growth of the women’s game in the United States, one of the few countries where women enjoy equal access and funding to the world’s most popular game. But without a pro league, continued growth and the continued expansion of women’s access is no guarantee.

There are plenty of challenges facing the league, but there was once a mountain of challenges facing the now-thriving men’s league, Major League Soccer, and unlike an American women’s league, it can’t claim that it has the world’s best players or top competition. That doesn’t mean that the women’s league will become a similar success story. That Gulati and the league’s investors are committed to making a women’s league viable and sustainable, though, is a good sign for the future of the women’s game and it’s biggest stars.

When the United States Women’s National Team kicks off its gold medal match against Japan tomorrow in London, it will mark the culmination of a year-long journey toward avenging its loss to Japan in last year’s World Cup final. The women’s team captured America’s heart last year before losing in heartbreaking fashion in Germany, and the run to the Olympics has been similarly dramatic — the U.S. defeat of Canada in the semifinal was hailed as one of the premier international matches in the sport’s history, and its systematic dismantling of the rest of its competition has been beautiful to watch.

Whether the U.S. avenges its World Cup defeat or falls short again, though, an uncertain and unfortunate future awaits the top American players. They will return next week to a United States that has no major professional soccer league after Women’s Professional Soccer (WPS) folded earlier this year, meaning the game’s biggest stars — Abby Wambach, Hope Solo, Alex Morgan, Megan Rapinoe, and others — will have no top-level soccer to play.

That’s a major problem, not just for the continuance of the American women’s dominance of soccer, but for the health of women’s soccer around the world. There are more than 337,000 American girls playing soccer on 10,500 high school teams alone; there are another 700 women’s college-level teams and hundreds of thousands more playing at levels below high school. The growth of women’s soccer around the world has followed the United States, where the USWNT remains one of the few fully-funded national teams. Brazilian star Marta played her professional games in the WPS, and even in soccer-mad countries across Europe, women have struggled until late to gain the same access to the game that they enjoy in the United States.

An America without women’s professional soccer, however, puts all of that in jeopardy. And there are plenty of reasons to worry about the future of women’s soccer: excitement about previous World Cup wins and mega-stars wasn’t sustained, and as popular as this rendition of the USWNT has been, there’s little evidence that American sports fans are ready to support a major women’s league. WPS drew just more than 3,500 fans per game in 2011, and its model — which included teams in six cities — proved unsustainable.

But there is good news, too: U.S. Soccer president Sunil Gulati is committed to growing and sustaining a major women’s league in the U.S., as he told Sports Illustrated columnist Grant Wahl this week. “We’ve talked with club owners and teams that are in the USL and teams in the WPSL,” Gulati told Wahl, referring to two American semiprofessional leagues that still exist. “And we’ll see what we can figure out, not on how we get the right set-up started, but on how we get the right set-up sustainable. That’s more important. Whether that’s an existing set-up or some other set-up or a combination, I don’t know yet.”

There is also precedent for reviving a failed soccer league in America. Major League Soccer got off to a bumbling start in the 1990s, drawing small crowds and expanding to new cities far too fast. After downsizing and reorganizing, the league is now thriving in 19 cities and drawing bigger crowds than ever. And unlike a women’s league, MLS can’t boast that it features the world’s best players.

As Gulati told Wahl, growing a domestic women’s professional league is going to take time and patience. Like MLS, it will have to start small, placing teams in strategic cities where soccer is already popular and facilities already exist, and partnering with well-established MLS teams in Los Angeles, D.C., Seattle, and New York (as some semiprofessional women’s teams already do) could help the league off the ground. MLS was once left for dead, too, and it is now thriving. And regardless of the constraints, starting, sustaining, and growing a major women’s professional league is imperative. The world’s biggest stars need a place to play, and the millions of soccer-playing girls around the world who dream of repeating the heroics of women like Wambach, Morgan, and Rapinoe need proof that their sport doesn’t lead them to a dead end.