Lydia Ko lost her sharpness in the second round of LPGA Thailand in Chonburi and paid for it with a drop down the leaderboard.
Lydia Ko of New Zealand in action during day one of the Sime Darby LPGA Malaysia at TPC Kuala Lumpur East Course in Kuala Lumpur.
Kiwi golfer Ko shot five bogeys in a two-over 74 to slip 16 places to 32nd on one-under.
The world former world No.1 lacked the precision of her opening 69 and is 15 shots off the pace at the midway point.
American leader Jessica Korda thrived at the Siam Country Club, shooting a 62 to power four strokes clear of second-placed compatriot Brittany Lincicome.
It is Korda's first tournament since undergoing jaw surgery to correct a severe overbite.
Her 16-under tally is a 36-hole record for the event.