Orlando Pride and United States forward Alex Morgan has called for the National Women’s Soccer League to end the “systemic failure” that enabled a decade of alleged sexual misconduct and harassment of players by a number of the league’s coaches.

Morgan’s remarks on Tuesday came days after the North Carolina Courage fired coach Paul Riley amid allegations of sexual coercion and inappropriate comments about players’ weight and sexual orientation.

On Thursday, the Athletic published claims of abuse made by former NWSL players Sinead Farrelly and Mana Shim in addition to more than a dozen players from every team Riley has coached since 2010.

“I’m here to support Mana and Sinead and to continue to amplify their voices, and just show the systemic failure from the league and how wrong they did in handling Mana’s case and complaint and investigation and where they failed Mana and Sinead, and probably many other women,” Morgan said on NBC’s Today show.

“When I look back, I tried to be as good a friend and teammate as possible to Mana in helping her file a complaint, when at the time there was no anti-harassment policy in place, there was no league HR, there was no anonymous hotline, there was no way to report.

“We’ve now started to put these things in place, by demand of players, not by the league being proactive. Something we ask is for the league to start being proactive, not reactive. We’re asking for transparency.”

Shim elaborated on the harassment she experience as one of Riley’s players, making a renewed call for better protection of athletes.

“He’s a predator. He sexually harassed me, he sexually coerced Sinead, and he took away our careers,” Shim said. “From early on, there was a possession not just from Paul but from the team that I was playing for. They silenced me for multiple issues, my sexuality being the most important one, and, yeah, I was just very, very uncomfortable the whole time.

“And every day I showed up to work, every day I practiced, every game I played, I didn’t have confidence and I was scared. The only thing that got me through was my teammates.”

Farrelly said that going on the record with her charges gave her “pain a purpose” and remains hopeful that real change will be the outcome.

“The support and the validation of this story by everyone globally has just been, has blown me away and really has felt like it has given my pain a purpose,” Farrelly said. “Mana and Alex and a couple of other women we worked with, and every person who’s reached out and shown support, has turned this moment into a movement and made this matter.

“They have truly amplified our voices and just made this what it should be, which is a huge deal, and demanding change.”

The allegations prompted the resignation off NWSL commissioner Lisa Baird after some 19 months on the job last week and the postponement of all matches scheduled for Friday and Saturday.

Additionally, Fifa on Friday opened an investigation into the case. It is rare that soccer’s international governing body gets involved in a controversy involving a member association. US Soccer also announced an independent investigation on Friday.

US Soccer was instrumental in founding the NWSL in 2013 and helped support the league until last year, when it became independent. The federation continues its financial support of the league.

“Player safety and respect is the paramount responsibility of every person involved in this game. That is true across every age, competition and ability level,” US Soccer president Cindy Cone said in a statement. “We owe it to each athlete, each fan and the entire soccer community to take every meaningful action in our power to ensure nothing like this ever happens again.”

Fifa told the Associated Press it was “deeply concerned” by the case and will now be seeking further details from American soccer authorities about the issues raised.

“Due to the severity and seriousness of the allegations being made by players, we can confirm that Fifa’s judicial bodies are actively looking into the matter and have opened a preliminary investigation,” Fifa said in a statement to the AP. “As part of this, Fifa will be reaching out to the respective parties, including US Soccer and NWSL, for further information about the various safeguarding concerns and allegations of abuse that have been raised.”

The alleged harassment of Farrelly started in 2011 when she was a player with the Philadelphia Independence of the now-defunct Women’s Professional Soccer league.

She told the website the harassment continued when Farrelly was with the Portland Thorns. Shim, a former Thorns player, also allegedly experienced harassment. The Thorns said Thursday that the team investigated claims about Riley and passed those on to the league when he was dismissed.

Riley told the Athletic the allegations were “completely untrue”.

Outcry over the allegations rocked the league and forced this weekend’s games to be called off. The NWSL Players’ Association said it hoped fans would understand and support the decision.

“It is OK to take space to process, to feel and to take care of yourself,” the union said. “In fact, it’s more than OK, it’s a priority. That, as players, will be our focus this weekend.”

On Tuesday, the NWSL’s players’ union issued a statement in support of the players and confirmed that matches would continue as scheduled.

“Today, we stand with Mana, Sinead, and Kaiya [McCullough] as they continue to tell their stories. We have made the decision to proceed with Wednesday night’s scheduled competition, but our demands will be forthcoming. #NoMoreSilence,” it read.