Nigeria came from behind to beat Australia and leave the co-hosts facing a battle to qualify for the last 16 of the Fifa Women's World Cup.
Australia scored first when Emily van Egmond converted Caitlin Foord's pass.
But Nigeria equalised soon afterwards with Uchenna Kanu's calm finish, before Osinachi Ohale's header made it 2-1.
Asisat Oshoala scored after a mix-up between Australia's Alanna Kennedy and Mackenzie Arnold and Nigeria held on, despite Kennedy scoring late on.
Nigeria move top of Group B, level with Canada on four points, while Australia are a point behind both before the last matches in the section on Monday.
Australia face Canada in Melbourne and would need a victory to guarantee a place in the knockout stages, while Nigeria will play already-eliminated Republic of Ireland at the same time in Brisbane.