IOWA CITY, Iowa (AP) — Four members of the Iowa women’s field hockey team have filed a federal gender bias complaint over the firing of their coach. As first reported by ESPN on Thursday, players Natalie Cafone, Chandler Ackers, Jessy Silfer and Dani Hemeon filed the complaint with the U.S. Department of Education last week. They allege the firing of coach Tracey Griesbaum is part of a pattern in which strong female coaches have faced discrimination and been fired.

Athletic director Gary Barta fired Griesbaum in August, after an investigation into allegations of verbal abuse by former players. The university has defended the firing, saying Barta took action to protect players. But Griesbaum’s supporters say she’s done nothing wrong and is the victim of a double standard.

University officials have repeatedly rejected gender bias claims.