Five-time champion Lin Dan and women's top seed Akane Yamaguchi of Japan were both upset in the second round of the World Championships on Tuesday.
Yamaguchi, who won the bronze in last year's edition, slumped to a 21-14, 21-18 defeat to the 20-year-old Yeo in just 40 minutes.
"I could not get into my rhythm. I was surprised by the opponent and got lured into her style of playing," said Yamaguchi, who became the first Japanese to win the Asian Championships women's singles title last April.
"I was not in peak condition and I did not reach some parts of the court as fast as I usually do."
The 22-year-old became the second big name on the day to make early exits following China's Lin, who was stunned by India's 30th-ranked H.S. Prannoy 21-11, 13-21, 21-7.
It was Lin's earliest exit in his 12 appearances at the World Championships. He was defeated twice previously in the third round -- in 2003 when he played for the first time at the age of 19 and last year in Guangzhou, south China.
"I don't have enough energy in today's match, especially in the first set," he said. "I played better in the second but in the third I just ran out of energy."
Lin, who turns 36 in October, blames organizers for "unfair" arrangement of the match schedule, which gave him mere 15 hours to recover from the first round match.
His teammate Lu Guangzu was beaten by 14th seed Lee Zii Jia 12-21, 21-14, 21-15, leaving reigning Olympic champion and third seed Chen Long the only Chinese player in the men's singles draw. Chen, who won the world title in 2014 and 2015, takes on Lee Cheuk Yiu of Hong Kong, China on Wednesday.
Defending champion and world No. 1 Kento Momota of Japan cruised into the last 16 with a comfortable victory over Luis Enrique Penalver of Spain 21-10, 21-7.
Eighth seed Kenta Nishimoto, also of Japan, advanced by beating Chinese Taipei's Tang Tzu Wei 25-23, 13-21, 21-16.
In the women's draw, China's sixth seed He Bingjiao beat Japan's Aya Ohori 21-15, 18-21, 21-12 while her teammate and 13th seed Han Yun defeated another Japanese player Sayaka Takahashi.
Thailand's seventh seed Ratchanok Intanon beat Nitchaon Jindapol 22-20, 21-14 in an all-Thai affair.
