The result has been described as one of the biggest upsets in the event's recent history, with Tze Yong proving the "Mission Impossible" billing wrong with the 15-21, 21-9, 23-21 victory at the Arena Birmingham.

Denmark's Axelsen, who currently holds the Olympic and world titles in the discipline, looked a different player as he moved sluggishly around the court.

"This is the biggest win of my career," said Tze Yong, who was making his first appearance at the Open.

"I just kept concentrating on every single point and tried not to make simple mistakes.

"I tried not to focus on him, I just wanted to play as consistently as possible.

"It's my first time at All England but my second time in Birmingham after the Commonwealth Games, I feel very excited to be here."

The defeat was Axelsen's fourth in 61 matches.

In Super 1000 tournaments, he has won 45 of his last 47 fixtures.

He is the fourth seeded player to be eliminated so far in the men's singles tournament alongside Indonesian Jonatan Christie, Chou Tien-chen of Chinese Taipei, and Singapore's Loh Kean Yew.

In contrast, the women's singles matchups went largely as expected.

The second seed and 2022 champion An-Se Young of South Korea annihilated Chinese Taipei's Pai Yu-po 21-3, 21-7.

It means that she faces Spanish champion from 2015 Carolina Marín, who downed American Beiwen Zhang 21-13, 21-18 after 41 minutes.

Defending champion and top seed Akane Yamaguchi of Japan and three-time champion, Chinese Taipei's Tai Tzu-Ying, were also largely untroubled as they reached the last eight, as were China's He Bingjiao and Chen Yufei.

Only one unseeded player, Gregoria Mariska Tunjung, remains in the draw after her victory over Thailand's Lalinrat Chaiwan, becoming the first Indonesian to reach this stage in women's singles in ten years.