Ami Matsuo was recently approached to swim for Japan but will race for Australia.
One of the rising stars of Australian swimming is gaining a reputation around the world.
Artarmon teenager Ami Matsuo is back in Sydney and in training for next year's Commonwealth Games.
The 17-year-old was recently approached to swim for Japan but said her decision was an easy one.
"I was born in Australia and grew up here so I think of myself as Australian," she said.
At the recent World Championships in Barcelona, Ami was given a surpise birthday celebration by the Australian team.
"On the last day, James Magnussen came out with a birthday cake and they all sang ‘Happy Birthday’ for me and I think it was one of my best birthdays ever," she said.
Many are predicting the teenager has gold in her future.
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