The Women's United Soccer Association (WUSA), the first-ever professional women's soccer league in the world, folded after its third season. Its successor, Women's Professional Soccer (WPS), folded after its third season. The latest iteration of stateside female pro soccer, the National Women's Soccer League, enters its third season on Friday.

Here's some more anecdotal evidence that might induce worry, if presented entirely free of context: The WUSA and WPS collapsed after their 2003 and 2011 seasons, respectively. Those were both Women's World Cup years. 2015 is also a Women's World Cup year.

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But the NWSL isn't anything like its predecessors. Following the wild success of the 1999 Women's World Cup here in the United States, the WUSA launched with much fanfare and bloated budgets. From the first day until the last, it hemorrhaged money. The WPS was more modest in its business model but still paid out fairly sizable salaries to star players; that didn't work either.

So the NWSL is, by comparison and any other measure, a fairly bare bones operation. For an upstart women's soccer league, this is simply a market-mandated necessity.

Cognizant of the need to have a healthy professional women's league in North America – as competitors spring up around the world and help develop better national teams – the soccer federations of the U.S., Canada and Mexico agreed to cover full-time salaries for their national teamers active in the NWSL. By essentially writing off the big payroll hits for its most famous players – probably its largest cost by far – the league's chances of survival instantly multiplied.

"The most certain way that we avoid that fate [of preceding leagues] is the relationship and the commitment from our federation partners," said new commissioner Jeff Plush, a long-time sports and soccer executive who was installed in January. "It completely changes the dynamic of what the last two leagues had going against them."

Like any startup business, it's difficult to get a sense of viability at the dawn of its third year. When there are issues, are they growing pains or early signs that the product simply isn't in demand?

The NWSL has no shortage of challenges. Almost all of its nine teams play in tiny venues to anemic crowds. While the Portland Thorns have gotten an average of 13,300 people through their gates in each of their first two seasons, most clubs are closer to the Sky Blue FC's figure of 1,600 in Piscataway, N.J. Television deals have been meager – the little-watched Fox Sports 2 showed six regular season games and all three playoff games in 2013; and in 2014, ESPN2 aired three regular season games and the three-game playoffs, and online-only ESPN3 put on three more games. Lacking national or even local television exposure, clubs mostly broadcast their own games through YouTube.

Salaries, meanwhile, are microscopic. The entry-level class of players makes $6,000 per season. And players who aren't on the national team payrolls top out at $30,000, making it hard for them to stay in the league once they pass their mid-20s and expect a little more comfort in life.

There are few foreign superstars coming over anymore, the way they did in the WUSA and WPS. In fact, plenty of NWSL players go abroad in the offseason, ostensibly to stay in playing shape, but probably just as much to draw a few more paychecks. U.S. star Abby Wambach decided to skip the club season altogether to spare her battered body for the World Cup.

Yet Plush speaks of his league with an infectious optimism and an unbridled ambition – about gaining real relevance in local markets and even creating youth development academies.

"It's in good shape," he said of his league. "It's an exciting time. The Women's World Cup brings that much more focus to our sport, which is excellent."

He argues that soccer's remarkable growth in America, where it is now entrenched in the mainstream, has created sufficient demand to support his league. Plenty of members of the women's national team have become bona fide stars, promising to draw new fans to the stadiums following the World Cup.

The trick this year as well as in 2016, when the U.S. women will presumably defend their Olympic title again, is to leverage the World Cup for all it's worth. Although it will drain the most high-profile talent from the league for the first half of the season as players attend various camps, tune-up games and then the tournament itself – missing as many as half their club's regular season – it offers significant opportunities.

"We have to embrace it rather than fight it," says Plush, who expects 50 of the league's players to represent 10 countries. "That's just a massive celebration of our game and we have to take advantage of that both in the run-up to the World Cup as well as during and after."

The NWSL intends to utilize its partnership with U.S. Soccer and Nike, which sponsors both parties, to facilitate crossover advertising for ticketing promotions, social media campaigns and viewing parties. There'll be plenty of organic interest. "Then it'll be our job to execute against that," Plush says.

Still, caution is first and foremost – a crawling growth rate is how Major League Soccer survived its turbulent first decade as well.

"You have to have the proper dynamics and the proper platform to be successful long-term," Plush said. "And that's very prudent on the expense side, very responsible on your revenue projections. I think we are equally ambitious from what the other leagues were but we take some lessons from past mistakes."

Yet while the league remains careful and years from maturity, as is plain to see when you attend a game, it could grow in the coming seasons. Plush claims expansion talks are ongoing.

"We're in various stages of dialogues, from introductory to advanced, in a variety of cities," he said. "I'd be pretty confident there will be an expansion announcement by the summer. The interest level is high."

Much of that interest comes from men's pro soccer clubs. Plush figures the league will expand from nine to 12 teams "in the next couple of years."

The NWSL is also on the verge of signing and announcing another national TV deal, according to Plush. But this time around, it will likely be a multi-year deal, creating a long-term partner with a vested interest in doing right by the league.

This all sounds great. But then it's the job of the commissioner to exude confidence in his league's future. And with such a negative precedent set by predecessors, can all those challenges be overcome?

"It's a fair question to ask and it certainly historically makes a lot of sense," Plush said. "But I'll have a lot of pleasure when we're having the same conversation next year, heading into our fourth year."

Leander Schaerlaeckens is a soccer columnist for Yahoo Sports. Follow him on Twitter @LeanderAlphabet.

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