Round-up: The United States brought the Women's World Cup to life on Monday as they rose to the top of the 'Group of Death' with a 3-1 win over Australia in front of a raucous crowd.

A day after the Ivory Coast were humiliated 10-0 by Germany, Nigeria and Cameroon restored African pride while Japan opened the defence of their title in Vancouver with a 1-0 win over Switzerland.

Cameroon, who were making their first World Cup appearance, looked right at home on soccer's biggest stage as Gaelle Enganamouit score a hat-trick to lead the 53rd ranked Les Lionnes to a 6-0 victory over South American debutant Ecuador.

Nigeria and Sweden, who have appeared in all seven women's World Cups, experienced some first up jitters in Winnipeg with Francisca Ordega grabbing a late equaliser for the Africans to earn a 3-3 draw in the so called 'Group of Death'.

No nation will face a tougher road to the final than those in Group D, which features three teams ranked in the top 10, the U.S. (2), Sweden (5), Australia (10) and the 33rd-ranked Nigerians, who are the top African nation.

"The Nigerian team is a praying team," said Super Falcons coach Edwin Okon, who knelt down to kiss the ground and pray after Ordega's goal. "We knew it is not over until it is over."

The first appearance by the U.S. created an electric atmosphere as fans flooded across the border, filling Winnipeg Stadium with an amazing combo of red, white and blue flag-waving crowd.

"A couple of players, I heard them as they were taking the pitch for warm-ups say, 'it's like we're playing at home'," said U.S. coach Jill Ellis.

"It was tremendous, they were behind us, the Outlaws were there and friends and family but there were fans, just fans of soccer it was great to have that kind of noise and support."

The U.S. did their part as they extended their unbeaten run over the Matildas to 25 games as Megan Rapinoe scored twice and keeper Hope Solo produced some dazzling early saves.

The victory set up an intriguing showdown with former coach Pia Sundhage's Swedish side on Friday.

Sundhage had spent five years with the U.S. team, leading them to two Olympic gold medals and a runner-up finish in the 2011 World Cup, before she returned to coach her native Sweden.

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