Charismatic Poomjaeng won the frame which put Thailand into the last eight.
England were knocked out of the Nongfu Spring World Cup in China in dramatic circumstances, despite beating the Republic of Ireland in their final group game.
Mark Selby and Stuart Bingham, the world’s top two players, beat Ireland 3-2, but finished third in Group D so missed out on a quarter-final place. Thailand’s Dechawat Poomjaeng and Thepchaiya Un-Nooh beat UAE 4-1 to finish level on points with England, and finished second having won the head-to-head match at the start of the week.
Thailand go through to meet Wales on Saturday, while group winners China B, comprising Zhou Yuelong and Yan Bingtao, will face Australia.
A jubilant Un-Nooh said: “It feels great because we’ve never qualified for the second round before. This is a first for Thailand. I feel like we need to shout very loud. Now we have got this far, we are not scared of anything.”
Poomjaeng, who won the last and decisive frame against UAE’s Mohamed Shehab, added: “Now we have confidence. I want to beat everyone now. The final is so far away, but we will do it. We never give up.”
Selby said: “We won four out of five games and still didn’t qualify. We had such a tough group.”
There was also an exciting finish in Group C, after Welsh duo Mark Williams and Michael White had beaten Australia 3-2 to top the group. That result meant outsiders Pakistan could qualify by beating Northern Ireland 5-0 and that was on the cards when they went 4-0 up.
But Gerard Greene beat Muhammad Sajjad in the last frame, which meant Australia’s Neil Robertson and Vinnie Calabrese scraped through, just a point ahead of both Pakistan and Northern Ireland.
A relieved Robertson said: “I wasn’t aware that Pakistan could qualify, until Mark Williams told me during our match. We didn’t do well in the first two matches but Vinnie has really improved as the week has gone on and I’m proud of him. He played a good frame against Mark Williams today which proved vital in the end. This event has been fantastic experience for him.
“Pakistan are unlucky not to go through because they’ve had a great tournament with two very good players. But I’m delighted we’ve made it ahead of them.”