Tokyo Olympics: Football Ferns embracing challenge of must-win clash against world champions after opening loss to Australia

Football Ferns captain Ali Riley is embracing the challenge of a must-win game against the world champions as their Olympic hopes hang in the balance.

The women's tournament got underway in Tokyo on Wednesday, with the Kiwis coming up short 2-1, against medal contenders Australia.

Up next, the daunting task of playing the powerful Americans, who themselves are facing a win or go home match, after suffering a shock 3-0 defeat at the hands of Sweden.

Riley says the US will be desperate, and the New Zealand squad is prepared to play the ultimate spoiler against the tournament favourites.

Tokyo Olympics: Football Ferns embracing challenge of must-win clash against world champions after opening loss to Australia

"It's a very quick turnaround and I think we need to be very specific with our preparation and our analysis [of tonight]," says Riley.

"You can't spend too much time thinking about this game because we need to prepare for the next one.

"We're going to have to be ready for a US team that is not used to losing two games in a row. 

"I'm not sure if they ever have, so I think they're going to want revenge and we will be that target."

The Ferns fought back gallantly against Australia after falling two goals behind inside 35 minutes against their trans-Tasman rivals, winning the second-half thanks to a late Gabbie Rennie goal.

Coach Tom Sermanni praised his young charge, who came on as a replacement, and notes both Rennie and her teammates will be better for the 90 minutes against the Aussies.

"It's great for any player to score a goal but to come out to the Olympics, first time, obviously very excited to make the squad, probably unsure if she was going to make the squad, and to then come on and score her first international goal, it's a special moment for her."

"Getting today's game under our belts was of benefit to us - it helps us to be more focused and understanding of what to expect in the next game."

New Zealand and the United States will play on the weekend.

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