Xu, part of the Chinese side which won team gold at last month's Olympic Games in Rio de Janeiro, was expected to reach at least the semi-finals but came up against a stern opponent in Wong, the seventh seed.

Wong took the opening game before Xu appeared to have seized the initiative by winning the next two.

The player from Hong Kong kept his composure, however, and eventually battled back before securing a stunning 13-11, 3-11, 6-11, 11-7, 5-11, 11-7, 11-4 victory.

He will clash with second seed Fan Zhendong in the semi-finals after the Chinese beat compatriot Zhu Yu 11-5, 11-4, 6-11, 8-11, 11-8, 11-6.

"I have never taken more than one game off Xu Xin in the past so I’m excited," said Wong. 

"This is the first Open for me after the Olympic Games. 

"I feel that at the Olympic Games Xu Xin played at the highest level, but maybe there is less motivation here so I caught him when he wasn’t playing quite as well. 

"Xu Xin today was not playing at his real level, in the last two games Xu Xin made more mistakes than me."

There were no such problems for top seed and Olympic champion and Ma Long and Zhang Jike.

They will meet in a repeat of the Rio 2016 gold medal encounter in the last four after both came through their respective quarter-finals.

Ma, the current world number one and world champion, cruised to a comfortable 11-9, 11-6, 11-8, 11-8 success against the tricky Vladimir Samsonov of Belarus.

Zhang, who lost out to his team-mate in the Olympic singles tournament, was made to work hard for his place in the next round as he battled to a 11-9, 8-11, 11-4, 13-11, 7-11, 3-11, 11-3 triumph over Ho Kwan Kit of Hong Kong.

In the women's singles draw, there was another shock result as defending champion Zhu Yuling of China suffered a 3-11, 11-9, 3-11, 11-8, 5-11, 11-8, 11-8 reverse at the hands of South Korean Yang Haeun, the ninth seed.

Yang's semi-final opponent will be world number one Liu Shiwen as she overcame Zeng Jian of Singapore in seven games, 10-12, 6-11, 9-11, 11-5, 11-9, 11-9, 11-5.