How the NWSL made American women's pro soccer history

The National Women's Soccer League is already the most successful outfit in the history of professional women's soccer stateside.

By the grace of merely making it to a fourth season, which kicks off on Saturday, it has outlasted the Women's United Soccer Association (WUSA), which burned through some $100 million in losses from 2001 through 2003, and Women's Professional Soccer (WPS), which also ran heavy deficits from 2009 until 2011.

It's a low bar, certainly. But clearing it is nonetheless worth celebrating.

"We are incredibly excited about where we are and know there is more to be done," Commissioner Jeff Plush said on a conference call. "But there's certainly tremendous interest in our league."

Historically, finding a model that makes women's professional team sports work in the United States has been fraught. The WNBA, of course, exists at the behest of the NBA's willingness to subsidize it from its own steady profits – a cynic might say as a form of community outreach. The NWSL, too, has been the beneficiary of immense investment from U.S. Soccer, which claims to have sunk in somewhere around $10 million over the life of the league. It does so primarily by paying salaries for its senior women's national teamers to play in it. It's that star power that has made the NWSL viable.

The rest of the talent pool – save for Mexico and Canada's national team players, who are also subsidized by their national federations – is on an impossibly strict budget. The salary cap in 2016 – excluding players from those three national teams – will be $278,000 per team for a 20-woman roster. And while that's a $13,000 increase from last year, it also mandates that no player shall make more than $39,700 for the six-month season. The league minimum is $7,200. Last season, it was $6,842. Truly.

U.S. national teamers are reportedly paid an NWSL salary of $54,000, in addition to their national team pay.

This might all seem draconian. And it kind of is, but that's what needed to be done just to ensure the survival of the league. To get to that fourth season. Ambitions were dialed down. Smaller stadiums were enlisted. Consequently, the product is a lot less glitzy. Then again: it's still here, four years on.

But a league can only survive for so long when it pays a lot of its players a sub-minimum wage, right?

"It's a very fair question," Plush said. "We continue to try and take things up each year [financially], and we have been successful each year. We know that there's certainly more to be done, especially at the lower end of the pay scale."

Plush added that the league is looking to create opportunities to supplement salaries with jobs in soccer camps and academies while the league might underwrite coaching courses and licensing exams for its players.

In the meantime, the NWSL is laying the foundation for stable construction. It announced on Thursday that it had renewed its broadcast deal with FOX Sports, ensuring that three regular season matches and all three playoff games will air nationally. That may not sound like much, but it's a start. Keep in mind that in its early years, Major League Soccer bought airtime on ESPN.

And the level of play continues to improve. "One thing that I enjoy about this league," said Vlatko Andonovski, head coach of FC Kansas City, which won the last two league titles, "is anywhere we go, it's a competition."

The biggest victory of all, perhaps, is not just that the NWSL is still around, but that its executives are slowly emerging from survival mode.

"We've talked about a 10-year plan," Plush said. "To get there, we need to show growth in all revenue streams. That would mean more people in more buildings. We need more sponsors. We want to get more games on air. And we want to see more growth in player development."

And whereas previous leagues lost teams left and right, the NWSL hasn't folded any and added two – the Houston Dash in year two and the Orlando Pride this season. There's even chatter about further expansion.

"The conversations are robust," Plush said. "There's many of them. We will have significant conversations at our May board meeting."

Yet a dark cloud hangs over the league as well. The U.S. women's national team is ensnared in an ugly labor war with the United States Soccer Federation and has refused to take the possibility of a work stoppage off the table.

"The NWSL is a separate thing, so we're committed to playing in the league," said U.S. co-captain Becky Sauerbrunn, who also plays for Kansas City.

Yet that isn't entirely so. When NWSL salaries are paid by U.S. Soccer, a strike would necessarily have some kind of impact on the league, too. And then there's the irrepressible question over whether any pro league can successfully tap into the enduring popularity of the women's national team, whose buzz and mainstream traction have been stubbornly un-transferrable.

But at the very least, the NWSL is off the life-support it began its existence on. Whether it will ever break even, let alone thrive, on its own strength remains questionable. But for now, professional women's soccer in the United States survives.

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