Champion Intanon ousted, top seed Li cruises
Li Xuerui from China in action against Li Han of China during Womens Single match in Badminton World Championship at Ballerup Super Arena in Copenhagen on August 28, 2014 - by Nils Meilvang
Intanon, 19, crashed out in the third round after succumbing to Japanese 16th seed Minatsu Mitani 8-21, 21-12, 21-18.
There appeared few early warning signs as fourth seed Intanon blitzed through the opening game but she came unstuck as Mitani stunned the title-holder by wearing down her off-colour opponent.
"She was quicker and faster in the second game. She made me nervous by defending my smashes so well. I was getting tired after long rallies," said Intanon, who explained that she had spent five days in hospital prior to the tournament with a temperature that peaked as high as 39.5 degrees Celsius (103.1 degrees Fahrenheit).
"I couldn't play at 100 percent just four days after leaving hospital. I was only around 50 percent," said the 2013 champion.
"I didn't think about the pressure of the title, I just come to play."
Mitani's reward for claiming the scalp of Intanon is a quarter-final against Korean fifth seed Sung Ji-hyun, a 21-10, 21-16 winner over Indonesia's Lindaweni Fanetri.
"After the second game I tried to simply play to my strengths, be patient and move around the court," said Mitani.
"I was confident of my physical state. I did a lot of running while I was out injured. I didn't think about strategy I just tried to play my best."
Earlier world number one Li blasted away 12th-seeded compatriot Han Li to 21-9, 21-17 to stride into the last eight.
"We're team-mates so we're quite familiar with each other," said Li afterwards.
"Even in Chinese team competitions she does quite well, she's not an easy opponent," added the top seed before calling out her upcoming opponent, India's Saina Nehwal.
On Wednesday Saina called for the Badminton World Federation (BWF) to reduce the number of entrants per country at international tournaments to curb China's dominance in the sport.
Top-ranked Li, one of four Chinese representatives in the women's draw, responded by saying: "Let her beat me first...she still has to face (Chinese players) whether there's two or three of us.
"Even if an opponent isn't in the Chinese team of course she can still win. If she's not strong enough then that's her own problem."
Saina, bronze medallist at the London Olympics, set up a showdown with Li in the quarters after overcoming a patchy start to claw her way past Japanese 13th seed Sayaka Takahashi 14-21, 21-18, 21-12.
Second seed Wang Shixian of China is also through to the last eight after thrashing Vietnam's Vu Thi Trang 21-12, 21-7 while Taiwanese eighth seed Tai Tzu-ying ended the run of Canada's Commonwealth champion Michelle Li with a 21-16, 21-11 win.
Former boys' junior world champion Wang Zhengming was the first man through to the men's quarters after the Chinese sixth seed saw off Hong Kong's Wei Nan 21-15, 21-18.
South Korean Son Wan-ho, the seventh seed, eliminated home hopeful and 10th seed Hans-Kristian Vittinghus 21-19, 21-12 but there was better news for Denmark as 14th seed Viktor Axelsen fended off Nguyen Tien Minh of Vietnam 21-16, 21-17.
Dutchman Eric Peng, conquerer of China's 11th seed Tian Houwei in round two, also reached the last eight with a 19-21, 21-18, 21-16 defeat of Thailand's Tanongsak Saensomboonsuk.