Kim was never behind in her morning match against Chinese Taipei's, Chun Wei Wu, but it was closely fought affair until Kim edged clear late in the encounter to win 3&2.
Her afternoon match against American Brooke Seay, who is playing in her sixth US Junior Girls Championship, was an even closer battle, in fact, Kim lost her opening two holes before fighting back to win the next two.
There was never more than a hole in it from there but when Kim birdied the 17th she took a 1 up advantage to the last only for her opponent to birdie the last and take the match into extra holes.
Seay would birdie the third extra hole to eliminate Australia's hopes of a second US Girls Junior Championship seven years after the win of Minjee Lee in 2012.
Perth's Maddison Hinson Tolchard, who had finished runner-up in qualifying earlier in the week, was the only other Australian in the field but she would go down in the opening round of knockout matches yesterday.
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