Malaysia's Lee Zii Jia savoured a "revenge" victory over Chen Long as the world number 13 moved into the All England badminton Championship semi-finals on Friday.
Lee stunned the Chinese two-time champion 21-12, 21-18 to end the number three seed's hopes of a memorable third title in Birmingham.
Chen, the champion in 2013 and 2015, had previously beaten six-time All England champion Lin Dan 21-17, 21-8 to progress into the quarter-finals.
But he was no match for Lee who was motivated to avenge the result the last time the two met at the Denmark Open in October.
The unseeded Malaysian needed only 49 minutes to breeze past Chen and keep alive his hopes of lifting the trophy for the first time.
"Last time I played against Chen I lost to him, so it felt like a case of revenge for me today," Lee said.
"So far I've been able to pick up a couple of upsets, and I don't really think too much about winning the match tomorrow. I'll just go in there and play my best."
Lee, 21, is bidding for his first BWF World Tour event title since the Chinese Taipei Open in 2018.
In the other men's quarter-finals, Viktor Axelsen bt China's Yu Qi Shi 21-15, 21-7.
Top seed Tien Chen Chou defeated Tzu Wei Wang 21-11, 21-12, while Anders Antonsen beat Rasmus Gemke 21-10 21-13
China's Chen Yufei, the reigning women's singles champion, came from behind to beat world number five Ratchanok Intanon 17-21, 21-15, 21-17.
The 22-year-old has already won titles in Switzerland, Thailand and Australia, as well as her All England triumph last year.
"Of course when I was one game behind in the match I felt under pressure, however I always thought I'd be able to come back into it," she said.
"I have the confidence to go all the way this week. I've been preparing very well for the competition so hopefully I can go on to win."