20 year old Hwan is in his second season on the Japan Golf Tour, winning just his third event on Tour when successful at last year's Gateway to the Open Mizuno Open.
32 year old Miyazato, one of the famed Miyazato family from Okinawa, has yet to win on the Japan Golf Tour, his previous best having come in 2008 when runner-up at the Canon Open.
Brad Kennedy leads the Australians through the 36 hole mark, the Gold Coaster making a fast start to round two before finishing with a round of 70 to be in a share of 10th position and three shots from the lead.
Neven Basic is in 26th position, Steve Conran and David Smail 36th and Paul Sheehan just scraping through to the weekend at even par.
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