Bangkok, Thailand: Defending champions China will face dark horse Thailand in the last four of the Uber Cup after a dramatic day in the women's event on Thursday while South Korea will play top seeded Japan in the semis.
Thailand edged into the final four, with Busanan Ongbamrungphan sparking jubilation among the home crowd by winning the final women's singles 9-21, 12-21 to seal a 3-2 win.
Star player world number four Ratchanok Intanon started the tie well for the home side, demolishing Indonesia's Fitriani Fitriani in the first game.
But the visitors won the next two points, before a Thai doubles pair clawed back a point and Busanan powered her team to victory.
"I am really happy that I can make one point for my team," 22-year-old Busanan said after the match, adding that the home support helped "a lot".
As for their chances against China, she said it would be "very tough."
"But I think everyone in my team can do it. I will try my best," she added.
China recovered from a nervy start to beat Denmark 3-1.
Mia Blichfeldt drew first blood, taking apart world number 5 Chen Yufei in the opening singles.
But 14-times Uber champions China came back strong, with Olympic champion Li Xuerui finding her rhythm in her comeback tournament to beat Natalia Koch Rohde 21-7, 21-9 in 30 minutes.
"I was definitely better prepared today," Li told organisers after the match.
Heavyweights Japan and South Korea complete the semi-final line-up, both also stuttering through their quarter-final ties on Thursday.
Japan's women clawed back a win following the first match 21-19, 21-16 defeat of world number two Akane Yamaguchi by Taiwan's Tai Tzu-ying, who ranks higher than her.
The top-seeds bounced back with doubles pair Yuki Fukushima and Sayaka Hirota tearing through their rivals in the next match, followed by a routine 21-11, 21-12 win by singles world champion Nozomi Okuhara.
South Korea also struggled to get started against Canada, but eked out three wins against their unfancied opposition.
Victory was sealed by 16-year-old An Se-young, who celebrated exuberantly after her 21-13, 19-21, 21-11 win in the third singles over Canada's Brittney Tam.
"I told coach Kim (Ji-hyun) that I would dance on court if I won," she said after the match, according to a Badminton World Federation press release.
The prestigious biennial event has brought together 16 top teams from five continents for a week of intense competition for the men's Thomas Cup and the Uber Cup which is contested by the women.