Campbell completed a red letter day for Australian women's sport in Japan, her victory coming not long after Samantha Stosur had won the Japan Open tennis title.
Campbell and Miyazato both recorded final rounds of three under 69 to move past second round leaders Miki Saiki and Akane Iijima with Campbell actually taking the outright lead when she birdied the 16th. Campbell dropped a shot at the par three 17th to slip back into a tie with Miyazato and Iijima before Iijima bogeyed her final hole to miss out on a chance in the playoff.
Miyazato secured her first event on the LPGA Tour earlier in the season when she won the Evian Masters and she also victorious at the Sankyo Women's Open last week on the Japan Ladies Golf Tour so this victory is significant for the 2002 Australian Amateur Champion.
Campbell's only other victory in seven years on the Japan Ladies Tour came in 2006 but she has been a consistent money earner there and has been in good form in recent weeks. Campbell had been inside the top twenty in eight of her previous ten starts this season suggesting a victory was not too far away.
Campbell earns 14 million or $A170,000 for her victory, taking her to 10th position on this season's money list.
Chris Campbell, the brother of Nikki, is currently in second position on the secondary Challenge Tour in Japan and is guaranteed a return to the Japan Golf Tour in 2010.
Completing a good week for the Australians, South Australian Tamie Durdin finished 6th.
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