Former Arsenal star Rachel Yankey has warned the Lionesses to prepare for a tough knockout game against Nigeria at the Women's World Cup. The Lionesses, who remain unbeaten in Australia and New Zealand, have secured a victory over China in their final group game. England secured a victory over China, emerging winners of Group D after winning all three games. The Lionesses, who were underdogs in their last visit to Brisbane, are expected to face the 11-time African champions in the highly anticipated clash in Brisbane next Monday. Yankey believes Nigeria's style of football will be tough, but she is pleased with the team's goals and the rotation of players. The last time the two countries met in the tournament was in the group stage 28 years ago, with the Lionesses edging the contest 3-2 to progress to the knockout stages.