Koepka had fallen off the pace he shared after day one when he slipped to 1 over through 12 holes but an eagle at the 13th followed by birdies at the 16th and 18th holes have him one ahead of South Korean Hyun-Woo Ryu and Japanese superstar Hideki Matsuyama.
Koepka is the defending champion and Matsuyama was the winner in 2014 and so the weekend promises a ding dong battle between the pair.
Kurt Barnes, who finished 3rd behind Koepka last year, recorded a round of 67 today to move into a share of 10th place as the leading Australian. Adam Bland is 17th, Brad Kennedy 21st and Matthew Griffin 48th were the other Australians to make the cut.
Barnes s is currently in 81st posit this week on the Japan Golf Tour's money list and so needs something special this week or next to avoid Tour School.
Brendan Jones was well enough placed with a few holes to go but a triple bogey at his 14th hole followed by a double at the last saw him miss the weekend by an agonising one shot.
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