The U.S. Women's National team in December 2015Eric Gay / AP

Five members of the U.S. women’s national soccer team filed a complaint Thursday with the Equal Employment Opportunity Commission (EEOC), demanding that the women’s team––who have outperformed their male counterparts in just about every metric possible in the past couple years––be paid just as much as the men.  

The players who signed the complaint against the U.S. Soccer Federation, the governing board of U.S. soccer, are some of the biggest names on the team, and in American women’s sports: Carli Lloyd and Becky Sauerbrunn, who are co-captains, the goalkeeper Hope Solo, the midfielder Megan Rapinoe, and the forward Alex Morgan.

A statement from their lawyer (sent to Sports Illustrated) said the men’s team earns almost four times more than the women’s squad. The New York Times broke that disparity down even further. Women on the team make a salary, and like men, are eligible for bonuses. And that’s about where similarities stop. A man makes $5,000 for a loss; women make nothing for a loss or a tie. Men earn as much as $17,625 for a win, The Times reported. Women make $1,350 for one.

The debate over pay mirrors a similar argument being played out in international tennis. Earlier this month, Raymond Moore, the CEO of Indian Wells Tennis Garden, appeared to deride women’s tennis, where the Grand Slams and some major tournaments offer equal prize money.

“You know, in my next life, when I come back, I want to be someone in the WTA [Women’s Tennis Association] because they ride on the coattails of the men,” Moore said. “They don’t make any decisions, and they are lucky. They are very, very lucky. If I was a lady player, I’d go down every night on my knees and thank God that Roger Federer and Rafa Nadal were born because they have carried this sport. They really have.”

He subsequently resigned amid the backlash, but his views are shared by at least some top men’s players. Novak Djokovic, the world’s No. 1 men’s player, suggested that professional tennis should pay men more because they attract high viewership. That argument notwithstanding, pay equality in tennis, as my colleague Adam Chandler reported, “isn’t a cut-and-dry issue. In Grand Slam tournaments, men have to win three sets to advance while their female counterparts have to win two.”

But that’s clearly not the case with soccer. For starters, both men’s and women’s games are 90 minutes long. Then, by most measures, the women’s team is not only more accomplished, but also more popular. The women have won three World Cups and four Olympic gold medals. The men have not come anywhere near that. And last July, the Women’s World Cup final set a record for TV viewers––for women’s soccer, and men’s.

The players’ lawyer, Jeffrey Kessler, said the complaint with the EEOC, which handles workplace-discrimination issues, is as strong as he has seen, “because you have a situation where not only are their work requirements identical to the men’s requirements—the same number of minimum friendlies they have to play, the same requirements to prepare for their World Cups—but they have outperformed the men both economically and on the playing field in every possible way the last two years.

“So this isn’t a case where someone can come in and say the reason the men are paid more is because they are more economically successful or the men outperform the women or they’re not comparable in the same way,” he said.

And it’s not just pay from U.S. soccer that is unequal. For a long time, the women’s team has complained that everything from the referees who call their matches, to the fields they play on, don’t compare with the men’s. Last December, the women canceled a game against Trinidad and Tobago in Hawaii because the artificial turf, they said, was peeling and laden with rocks.

U.S. Soccer said in a statement, sent to ESPN, that it hadn’t seen the specifics of Thursday’s complaint, but that it’s disappointed.

“We have been a world leader in women’s soccer and are proud of the commitment we have made to building the women’s game in the United States over the past 30 years,” the statement said.

Relations between the two sides have been fraught in recent years. In February, two months after the incident in Hawaii, U.S. Soccer sued the union that represents the women’s team in federal court, arguing the terms it agreed upon for its players, and that expired in 2012, should still be valid. The union says it doesn’t.

On Thursday morning, four of the players appeared on NBC’s Today show. Lloyd, one of the team’s captains, and who was also named the best player in last year’s World Cup, said, “I think that we’ve proven our worth over the years.”

It is unclear how long the EEOC will take to resolve the complaint, but the process will loom over the team’s preparations for the Rio Olympics in August, where the women are the favorite to retain their Olympic gold.

We want to hear what you think about this article. Submit a letter to the editor or write to letters@theatlantic.com.