The 40-year-old South Korean-born golfer fired a one-over-par round of 73 on Friday to sit at four-under in the $750,000 tournament, one of only a handful of players under par following a tough day at the Royal Jakarta Golf Club.
One of those was former world number one Lee Westwood, who celebrated his 42nd birthday by shooting a 74 to sit seventh at one-under.
Both Park and Westwood enjoyed slightly better conditions on Friday morning and watched as their names rose further up the leaderboard with the afternoon starters struggling their way around the tricky pin placements.
Joint overnight leaders Thomas Bjorn and Chan Shih-chang had begun the day at six-under but they quickly fell down the leaderboard.
Taiwan’s Chan recovered on his back nine, chipping in for eagle at the 18th to sign for a 75 to sit second on three-under, but Dane Bjorn struggled with the short stick and missed numerous putts from close range in slumping to a 76.
Bjorn’s card smartened up with back-to-back birdies to finish his round, including a neat chip in on the 17th, to sit two strokes behind the leader.
Former U.S. PGA champion Yang Yong-eun was one of few players to shoot under-par in the second round, firing a 71 to sit four shots back of Park.