The US women's national team has sued the US Soccer Federation for alleged gender discrimination, just three months before they open their FIFA Women's World Cup title defence in France.
All 28 members of the US squad were named as plaintiffs in federal court in Los Angeles on International Women's Day, with the lawsuit including complaints about wages and other working conditions.
The players, a group that includes stars Megan Rapinoe, Carli Lloyd and Alex Morgan, said they have been consistently paid less money than their male counterparts even though their performance has been superior.
The US women's team has enjoyed unparalleled success in international football, including three World Cups and four Olympic gold medals.
"Each of us is extremely proud to wear the United States jersey, and we also take seriously the responsibility that comes with that," Morgan said.
"We believe that fighting for gender equality in sports is a part of that responsibility. As players, we deserved to be paid equally for our work."
According to the lawsuit, filed three years after several players made a similar complaint with the US Equal Employment Opportunity Commission, US soccer has "utterly failed to promote gender equality."
The lawsuit outlines years of institutionalised gender discrimination, claiming travel conditions, medical personnel, promotion of games and training are less favourable for female players compared to male counterparts.
When the women's team clinched their most recent World Cup title in 2015, it was the most watched football game in American TV history, with an audience of approximately 23 million viewers.
The team's success has translated into substantial revenue generation and profits for the federation, the lawsuit said.
The US Soccer Federation did not respond to requests for comment.
FIFA announced on Friday plans to host a global women's convention this June in Paris where leaders from the world of sports and politics will discuss key issues around the development and empowerment of women in soccer.