SEOUL, May 9, 2013 (AFP) - Pilkadaris and Cho both capped blistering rounds with birdies on the ninth at The Namseoul Country Club to give them a three-shot lead over the chasing pack.
Pilkadaris said a change to his putting stroke contributed to his flawless round, while Cho said he scrambled well.
Thirty-nine-year-old Pilkadaris, whose last win came at the Brunei Open in 2005, admitted he had struggled around the hilly 6,349 metre (6,943 yard) course in the past.
"I only made the cut for the first time a couple of years ago ... I haven't had a good run here," he said.
"But the greens are also bit slower than they normally are; I had a couple of downhill putts that I managed to two-putt where in previous years you'd be lucky to do that."
Cho also gave his putter credit for an excellent round.
"My putting was really good today but actually the score looks better than the golf - I was scrambling a bit out there," he said.
The 24-year-old has played full time on the Japan Tour since 2010 -- winning the Kansai Open Golf Championship the following year -- and he finished joint fourth at March's Thailand Open.
Defending champion Kim Bi-O blamed a lapse in concentration on the last for a double-bogey that left him level par for the round.
"I felt a bit of pressure out there and was coping well, but I let it slip right at the end," he said.
Scores after round one: (par 72)
64 - Cho Min-Gyu (KOR), Terry Pilkadaris (AUS)
67 - Lee Kyoung-Hoon (KOR), Kim Do-Hoon (KOR), Matthew Griffin (AUS), Kim Hyung-Sung (KOR), Park Jun-Won (KOR)
68 - Song Young-Han (KOR), Park Ju-Hyuk (KOR), Park Eun-Shin (KOR), Kim Seng Yong (KOR), Kim Gi-Whan (KOR), Park Jae-Kyung (KOR), Kang Kyung-Nam (KOR), Peter Wilson (AUS), Park Il-Hwan (KOR), Kim Woo-Chan (KOR)