The Californian-based Korean posted a seven-under-par 64 to share the lead with Flint who also returned with a 64, while veterans Boonchu Ruangkit of Thailand and Chinese Taipei's Lu Chien-soon rolled back the years with matching 65s to take a share of third place with Singapore's Mardan Mamat.
Oh who has targeted this week's US$300,000 full field Asian Tour event for his first win on the Asian Tour is confident of achieving that after his early morning finish.Ã‚Â Ã‚Â
The 32-year-old is enjoying a welcome return to form, having finished in second and fourth in his last two events on the Asian Tour.
"I'm playing good and I'm giving myself a lot of birdie chances out there. I could have played a little bit better on hole two and especially hole four, where it was such an easy putt, being only four foot away," said Oh.
While the Korean was left to rue those easy birdie chances that could have seen him take the outright lead at the Empire Hotel and Country Club, he believes he will be ready to make up for those missed chances as the week progresses.
"I feel I can do better. I'm doing well on those tough ones but I'm letting those easy ones slip by. But I'm sure it'll get better," said Oh.
Meanwhile Flint was pleasantly surprised with his good form after carding a blemish-free round that was highlighted by seven birdies.
"I haven't been playing too well so today was a little bit of a shock. But I'm very happy to have put a good one on the board," said Flint whose best finish of the season was a tied-11th place at the season-opening Asian Tour International.
"I played well today. I hit the ball better and I putted well. I just want to stay consistent and hopefully have more birdies," added the Australian.
Boonchu proved that age is no barrier to success with a sparking performance despite nursing a hand injury.
"My palm was hurting a little when I started practicing today. Fortunately the greens were soft and I didn't have to exert too much strength when putting," said the Thai.
The 53-year-old fired a total of seven birdies against a lone bogey on the 220-yard par three seventh to stake a place among the leaders at the Jack Nicklaus-designed Empire course.
"It's always nice to be among the early leaders. But after playing golf for so long, anything can happen and you just have to stay patient," said Boonchu who is well respected in Thailand and across the region for his golf exploits where he has won five times on the Asian Tour throughout his illustrious career.
Fellow veteran Lu, a multiple winner of national Opens in Singapore, Malaysia, Thailand, India and a former OOM winner of the old Asian Tour in the 1980s, also produced a performance that defies his age
The 49-year-old marked his card with five birdies in his opening front-nine and another one on the par-five 12th in his inward nine.
"Simply unbelievable that I played so well today! I haven't been playing much as I've been getting frequent backaches due to my age. But an opening result like this is always good," said Lu.
Mardan, seeking his third victory on the Asian Tour, also got his campaign at the sultanate off to a strong start with seven birdies against a lone bogey on the par-five 15th.
"I've been striking my ball very well and most of my iron shots landed close to the pins. Those kinds of shots can really put you in an advantageous position," said the Singaporean and two-time Asian Tour winner.
Defending champion Rick Kulacz of Australia posted a 70 to take a share of 51st place.
"I hit some really good shots but just couldn't convert the putts today. I felt like I probably left a couple of missed chances out there. But I'm happy with my one-under score today. It's not too far behind and I'll try to put a low score in tomorrow morning," said Kulacz.
Source - Asian Tour
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