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The Watch Officetel: Lover Friend OnlineU.S. women's soccer team has a reputation for never giving up. If they happen to concede a goal or two, you can expect them to maximize every chance until they've closed the gap or taken the lead.

On International Women's Day, they showed that fighting mentality off the field when the team's 28 players sued the U.S. Soccer Federation for "years of ongoing institutionalized gender discrimination," according to a press release.

The suit is the latest phase in a battle for equality that launched in 2016 when the team's highest-profile players filed a wage discrimination complaint with the Equal Employment Opportunity Commission. The players, including Alex Morgan, Megan Rapinoe, and Carli Lloyd, argued that despite working as hard as -- and even outperforming -- the U.S. soccer men's team, they received less compensation.

The new suit alleges that not enough has changed. The women, who will defend their World Cup title this summer, are seeking an end to discriminatory practices as well as asking for back pay, damages, and attorney's fees, among other forms of relief.

“In light of our team’s unparalleled success on the field, it’s a shame that we still are fighting for treatment that reflects our achievements and contributions to the sport," Lloyd said in a statement. "We have made progress in narrowing the gender pay gap, however progress does not mean that we will stop working to realize our legal rights and make equality a reality for our sport.”

U.S. Soccer Federation has yet to respond to Mashable's request for comment, though it told NBC News that it doesn't comment on pending litigation.

The suit draws on the 2016 complaint by again pointing out that the women's team has previously brought in substantially more revenue than the men's team and yet earned significantly less for their work and achievements, which include multiple world championship titles. (The men have never won a World Cup or Olympic gold medal.)

At the time of the EEOC wage complaint, the female players could earn a maximum salary of $72,000 plus bonuses for winning certain matches or making it to the World Cup or Olympics. One comparison of the wage disparity, included in the new suit, suggests that if both the men's and women's team had played and won the same number of friendly matches in a single year, the female players would earn a maximum of $99,000 per year whereas the men would get an average of $262,320.

Part of this massive gap had to do with the separate bargaining agreements struck by each team. The men, who could rely on large salaries thanks to gigs with Major League Soccer, settled on a lucrative bonus structure. The women, on the other hand, couldn't count on their professional league, the National Women's Soccer League, for a competitive annual income and sought that instead from U.S. Soccer, in addition to securing paid maternity leave.

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Yet even after the women's team got closer to equal pay with a new collective bargaining agreement in 2017, the federation allegedly rejected the players' requests for compensation equal to what the men received, according to the suit. Following the 2016 complaint, a representative for the federation reportedly said, “market realities are such that the women do not deserve to be paid equally to the men.”

That's a predictable, common argument against equal pay, but the new suit undermines it considerably. As the suit reminds the public, the women have clearly demonstrated they can bring in more revenue than the men; in the 2016 fiscal year, their World Cup victory was largely responsible for taking a projected combined net loss of $430,000 for both teams and turning it into a profit of more than $17 million.

The suit also outlines the many ways in which the women still inexplicably get less, all around, than the men. This includes how women frequently play on a dangerous artificial surfaces when the men do not, fly commercial when the men travel by more convenient, comfortable charter flights, and the alleged allocation of fewer resources to promote women's games compared to men's.

That last point is critical: If U.S. Soccer Federation doesn't equitably invest in promoting the women's team, the players have no shot at drawing the crowds and interest that will consistently generate revenue comparable to what the men's team earns.

Additionally, paying them less because soccer fans sometimes prefer to watch men play isn't a reflection of the true value of the women's team. Instead, it's just more evidence of how female athletes -- and non-athletes, too -- can put in the same amount of work as men and still suffer professionally and personally thanks to entrenched cultural attitudes about whether they are as exciting or competitive or talented as men.

It's no wonder that when the players requested and received the right to sue from the EEOC, they seized the opportunity. Some of their critics will say they don't deserve what they seek, or that they should just be grateful for the incremental gains they've already won. But surrender would be out of character for a group of players long known for their ability to persist despite setbacks that, for other teams, would spell defeat.

Rapinoe said it best in her statement about the suit: “We feel a responsibility not only to stand up for what we know we deserve as athletes, but also for what we know is right – on behalf of our teammates, future teammates, fellow women athletes, and women all around the world."