Akani "Sunny" Songsermsawad gave Thailand's six strong team a flying start when the 6-red World Championship began at the BCC Hall at CentralPlaza Lardprao yesterday.
But Thepchaiya Un-Nooh failed to rise to the occasion when he faced defending champion Mark Williams of Wales.
Akani was involved in a thriller against England's Jimmy Robertson, the world No. 36.
The Thai fell behind 3-1 and 4-3 but won the contest 5-4. He produced his best when it mattered most, a break of 67 in the decider.
Thepchaiya, who lost 8-2 to Williams in last year's final, was this time beaten 5-1, the Welshman winning the last four frames.
"I'm lacking match practice but really played OK," said Williams who has now won 12 successive matches dating back to his first 6-red world title last year.
Victories at the 2017 World Championship and World Open made him a triple world champion with three unique world titles.
Thepchaiya's performance was a big disappointment to his Thai fans. He scored only 42 points in four frames and just one in the fourth.
Two players needed around the hour mark to complete whitewashes against their opponents.
England's Kyren Wilson won 5-0 against Marvin Lim Chun Kiat of Singapore in 57 minutes while Scotland's Graeme Dott took a shade longer, 65 minutes to beat Welshman Michael White by the same margin.
Dott showed no signs of the stomach illness that confined him to his room on Sunday as he scored 183 points in the five frames played compared to White's tally of 66.
England's Ricky Walden, the 6-red winner in its inaugural year in 2008, was up against it before he faced Tom Ford, the world No.32.
Walden's cue and case went missing on his flight from Paris.
He lost to Ford 5-4 despite leading 4-3 using the cue of Stephen Maguire who played later.
"I'm not happy with it but it's better than nothing and I must thank Stephen for letting me borrow his cue," said world No.28 Walden.
The total prize money of the tournament is 10 million baht, making it the richest cuesport event in Southeast Asia.
The winner will take home 3.5 million baht while the runner-up pocketing 1.3 million baht.
The first round battle will continue until tomorrow.
