Peter Uihlein fired his best round of the season to take a one-shot lead on day one of the True Thailand Classic Presented by Chang.
The American showed no signs of rust after a week away from the golf course as he recorded an excellent eight under par 64 to lead the way from Pelle Edberg.
The Swede is a familiar face at Black Mountain Golf Club courtesy of his affiliation with the Hua Hin layout, which is now a member of the network of European Tour Properties, and he held the lead at nine under after a blistering opening 15 holes.
But two bogeys in his last three handed the initiative back to Uihlein, who also held the first-round lead in his last appearance on The European Tour at the ISPS HANDA Perth International.
Uihlein's tie for fourth in Australia was his second consecutive top ten finish as he continues his recovery from a wrist injury, and the 26 year old is feeling refreshed after a recent break in Phuket.
"Last week I had a nice vacation, didn't touch a club which was nice," he said. "I just rocked up here. You come up here with a clean slate and a fresh start.
"I hit it so bad on Monday, Tuesday and Wednesday, so I was kind of bummed. So it's nice to do this today. Once the tournament got going, I just relaxed.
"It's nice staying back rather than going home after Australia."
Starting on the tenth, he made a birdie-birdie start but dropped a shot on the 12th before further gains on the 13th, 16th and 17th saw him turn in 32. Birdies then followed on the first, second, sixth and seventh as he equalled the course record set by Northern Ireland's Michael Hoey last year.
I’m pleased, I putted well and the putter is still hot which is nice. I hit some good wedges, some good iron shots. It was good - Peter Uihlein
Edberg also started on the tenth and turned in 30 as he made a hat-trick of birdies from the 12th and then made five in a row from the 16th to grab a share of the lead.
He saw birdie putts brush the hole before he made another gain on the par five sixth, but a bogey on the next and his closing hole saw him fall to seven under.
That put him one shot clear of Scotland's Scott Jamieson and Spaniard Javier Colomo.
Jamieson also had a run of five birdies from the 16th plus another gain on the sixth, while Colomo picked up shots on the first, sixth, seventh, 11th, 17th and 18th.
Home duo Pariya Junhasavasdikul and Prayad Marksaeng were then at five under alongside the English pair of Gary Boyd and Robert Dinwiddie, Welshman Rhys Davies, Taiwan's Hsieh Chi-hsien, American David Lipsky, South African Shaun Norris and Scotsman Simon Yates.
Australian Jason Scrivener recorded the 11th hole-in-one of the season on the par three third on his way to a level par 72.