The fifth seeded 23-year-old Thai ace won the 78-minute women's singles quarter-final encounter with a cool approach and refused to be intimidate by the second seeded Spaniard's shrieks and some mumbling 'mantra' in her 22-20, 13-21, 21-18 win. Marin was even called up by the umpire in the rubber set.
It is a bad start for Marin this year. Last year the 23-year-old Marin, apart from winning the gold in the Rio Olympics, failed to win a Super Series title while Ratchanok notched three Super Series titles in a row – the India Open, the Malaysia Open and the Singapore Open.
In the semi-final Ratchanok will face Japan's Akane Yamaguchi. The seventh seeded Japanese battled for 88 minutes in her 21-23, 21-14, 22-20 win over China's No 4 seed Sun Yu.
Top seed and world No 1 Tai Tzu Ying outplayed Rio Olympics silver medallist and world No 6 P.V. Sindhu of India 21-14, 21-10.
It was a bad day for India in Birmingham when No 8 seed Saina Nehwal was also shown the exit. The Indian, ranked No 9 in the world was edged out 20-22, 20-22 by third seed Sung Ji-hyun of Korea.
Meanwhile, Malaysia's Lee Chong Wei, the world No 1 and top seed, booked his place in the last four with an impressive 21-12, 21-12 win over China's seventh seed Tian Houwei in 45 minutes. The head to head count now stands 2-1 in Chong Wei's favour.
In the semi-finals, Chong Wei, a three-time champion, will meet Taiwan's Chou Tien Chen who ended Tanongsak Saensomboonsuk's run with a 21-19, 16-21, 21-18 win over the unseeded Thai. Taanongsak had ousted Olympic champion Chen Long in the second round.
Five-time world champion Lin Dan lived dangerously before marching into the semi-finals with a come-from-behind 8-21, 21-14, 21-15 win over Denmark's third seed Viktor Axelsen in 69 minutes. Axelsen is the reigning World Super Series champion.
It was also sweet revenge for the 33-year-old Lin Dan who lost to the lanky Dane in the bronze medal playoff in the Rio Olympics. He will face compatriot Shi Yuqi for a place in the final.
World No 1 and top seeds Goh V Shem-Tan Wee Kiong of Malaysia were also knocked out in the men's doubles. The Malaysians fell to a 21-19, 17-21, 21-19 defeat to China's Li Junhui-Liu Yuchen in 66 minutes.
The Chinese will face Japan's Takeshi Kamura-Keogo Sonoda who beat China's Liu Cheng-Zhang Nan 21-23, 21-15, 21-19 .
Indonesia's Marcus Fernaldi Gideon-Kevin Sanjaya Sukamuljo will face Denmark's Mads Conrad Petersen-Mads Pieler Kolding in the semi-finals.
Rio Olympics gold medal winners Tontowi Ahmad-Liliyana Natsir were upset 16-21, 21-19, 21-12 by England's husband and wife team of Chris Adcock-Gabrielle Adcock in the mixed doubles quarter-finals.
Malaysia's Rio Olympics silver medallist Chang Peng Soon-Goh Liu Ying rode to a 23-21, 21-14 win over China's unseeded pair Wang Yilyu-Huang Dongping and will face Japan's rising stars Yuta Watanabe-Arisa Higashino in the last four.
RESULTS ALL QUARTER-FINALS
(SINGLES) – Second Round
Men
Lee Chong Wei (Mas) beat Tian Houwei (Chn) 21-12, 21-15
Lin Dan (Chn) beat Viktor Axelsen (Den) 8-21, 21-14, 21-15
Chou Tien Chen (Tpe) beat Tanongsak Saensomboonsuk (Tha) 21-19, 16-21, 21-8
Shi Yuqi (Chn) beat Kazumasa Sakai (Jpn) 21-13, 21-4
Women
Tai Tzu Ying (Tpe) beat P.V. Sindhu (Ind) 21-14, 21-10
Sung Ji-hyun (Kor) beat Saina Nehwal (Ind) 22-20, 22-20
Akane Yamaguchi (Jpn) beat Sun Yu (Chn) 21-23, 21-14, 22-20
Ratchanok Intanon (Tha) beat Carolina Marin (Spn) 22-20, 13-21, 21-18
Men's doubles
Li Junhui-Liu Yuchen (Chn) beat Goh V Shem-Tan Wee Kiong (Mas) 21-19, 17-21, 21-19
Liu Cheng-Zhang Nan (Chn) beat Takeshi Kamura-Keigo Sonoda (Jpn) 21-23, 21-15, 21-19
Marcus Fernaldi Gideon-Kevin Sanjaya Sukamuljo (Ina) beat Chai Biao-Hong Wei (Chn) 21-16, 21-18
Mads Conrad-Petersen-Mads Pieler Kolding (Den) beat Lu Kai-Zheng Siwei (Chn) 21-12, 11-21, 21-16
Women's doubles
Kamilla Rytter Juhl-Christinna Pedersen (Den) beat Naoko Fukuman-Kurumi Yonao (Jpn) 21-12, 21-11
Jung Kyung-eun-Shin Seung-chan (Kor) beat Shiho Tanaka-Koharu Yonemoto (Jpn) 21-19, 21-17
Bao Yixin-Yu Xiaohan (Chn) beat Yuki Fukushima-Sayaka Hirota (Jpn) 21-11, 21-14
Chang Ye-na-Lee So-hee (Kor) beat Luo Ying-Lu Yu (Chn) 21-17, 21-8
Mixed doubles
Chris Adcock-Gabrielle Adcock (Eng) beat Tontowi Ahmad-Liliyana Natsir (Ina) 16-21, 21-19, 21-12
Lu Kai-Huang Yaqiong (Chn) beat Joachim Fischer Nielsen-Christinna Pedersen (Den) 21-14, 18-21, 21-11
Chan Peng Soon-Goh Liu Ying (Mas) beat Wang Yilyu-Huang Dongping (Chn)23=21. 21-14
Yuta Watanabe-Arisa Higashino (Jpn) beat Yoo Yeon-seong-Kim Ha-na (Kor) 21-17, 18-21, 22-20
