THE US Soccer Federation apologised on Wednesday night after it contended in court documents that women on its national team had lesser responsibilities and physical abilities than their male counterparts, an assertion that drew widespread criticism and sparked a player protest.

The statement from USSF president Carlos Cordeiro came hours after the Coca-Cola Company denounced the federation for its stance. Cordeiro also announced a shake-up of the USSF legal team.

“On behalf of US Soccer, I sincerely apologise for the offence and pain caused by language in this week’s court filing, which did not reflect the values of our federation or our tremendous admiration of our women’s national team,” the statement said. “Our WNT players are incredibly talented and work tirelessly, as they have demonstrated time and again from their Olympic gold medals to their World Cup titles.”

US players wore their warm-up shirts inside out for the national anthems and team photo before a 3-1 win over Japan in an Olympic prep match. Players hid the USSF crest on the jerseys but allowed the four stars — one for each World Cup title — to be visible.

“I think it just was a powerful message,” said forward Carli Lloyd, a two-time Fifa Player of the Year.

The players issued a group statement that was released by Molly Levinson, a spokeswoman for the players in their lawsuit: “We wanted to stand together as a team and make a statement on behalf of all women and girls that the federation‘s comments are unacceptable. We love this sport and this country, and we cannot stand for this misogynistic treatment.”

Coca-Cola had called the federation’s assertion in documents filed earlier this week “unacceptable and offensive.”

“We have asked to meet with them immediately to express our concerns. The Coca-Cola Co is firm in its commitment to gender equality, fairness and women’s empowerment in the United States and around the world and we expect the same from our partners,” Coca-Cola said in a statement, first reported by The Wall Street Journal on Wednesday.

Coca-Cola has been a long-term partner with the USSF as well as a global sponsor of the World Cup since 1974.

In court documents filed on Monday in response to the players’ motion for a summary judgement, the USSF said the women claimed their ability level is the same as the men “by ignoring the materially higher level of speed and strength required to perform the job of an MNT player.”

“A reasonable juror could conclude that the job of MNT player requires materially different skill and more responsibility than plaintiffs’ job does, while also taking place under materially different working conditions,” USSF lawyers wrote. “The job of MNT player (competing against senior men’s national teams) requires a higher level of skill based on speed and strength than does the job of WNT player (competing against senior women’s national teams).”

Levinson said: “This ‘argument’ belongs in the Paleolithic era.”

“It sounds as if it has been made by a caveman,” she said in a statement. “Literally everyone in the world understands that an argument that male players ‘have more responsibility’ is just plain simple sexism and illustrates the very gender discrimination that caused us to file this lawsuit to begin with.”

In addition to apologising, Cordeiro said the USSF had retained the law firm of Latham & Watkins, the firm where former USSF president Alan Rothenberg is a retired partner. Seyfarth Shaw had been representing the federation.

“I have made it clear to our legal team that even as we debate facts and figures in the course of this case, we must do so with the utmost respect not only for our women’s national team players but for all female athletes around the world,” Cordeiro said.

Players filed the gender discrimination lawsuit in federal court in Los Angeles last year, claiming they were paid less than their counterparts on the men’s national team. The women are seeking more than $66 million (£52m) in damages under the Equal Pay Act and the Civil Rights Act of 1964, and a trial is scheduled for May 5.

Both sides have moved for summary judgements, asking US District Judge Robert Gary Klausner to decide in their favour without a trial.

The USSF says disparities in pay between the men and women are the result of separate collective bargaining agreements with different terms. The women’s team receives salaries and benefits the men don’t.