The Malaysian, who competes independently and is not part of the national team, stunned Indian fifth seed Kidambi Srikanth 21-18, 21-18 to reach the quarter-finals at the Nanjing Olympic Sports Centre.

"It is my best performance after the French Open win [in 2012]," he said. 

"Of course I used to imagine that I could come this far - I've even imagined being world champion - but it's about achieving it, right? 

"Everyone imagines these things, but it's about doing the right things."

A dream quarter-final tie between the reigning world and Olympic champions in the men's singles was also confirmed today.

Denmark's top seed and defending champion Viktor Axelson beat Hong Kong's Ng Ka Long Angus 21-19, 21-8 while Chen Long of China defeated Kenta Nishimoto of Japan 21-18, 21-19.

The duo will lock horns tomorrow.

China's five-time champion Lin Dan was beaten 21-15, 21-19 by fellow countryman Shi Yuqi elsewhere in the draw.

Two replays of recent World Championship finals were also set-up in the women's singles quarter-finals.

Japan's reigning champion Nozomi Okuhara will face India's PV Sindhu in a repeat of the 2017 final while another Indian in Saina Nehwal will play Carolina Marin in a repeat of the 2015 gold medal match.

Nehwal beat 2013 world champion Ratchanok Intanon of Thailand 21-16, 21-19 while Olympic champion Marin cruised past Sayaka Sato of Japan 21-17, 21-13. 

Okuhara overcame Goh Jin Wei of Malaysia 23-21, 21-13 and Sindhu beat Sung Ji Hyun of South Korea 21-10, 21-18.

Top seed Tai Tzu Ying of Taiwan also progressed with a 21-19, 21-14 victory over United States' Zhang Beiwen.