British number one Cameron Norrie was knocked out of the Madrid Open as China's world number 99 Zhang Zhizhen's history-making run continued.
Zhang - the first Chinese man to break into the top 100 - had never before recorded an ATP Masters 1000 win prior to this year's tournament in Madrid.
But the 26-year-old battled back from a set down to stun Norrie, ranked 13th, with a 2-6 7-6 (7-2) 7-6 (7-2) win.
He is the first Chinese man to reach round four at a Masters 1000 event.
Meanwhile, it is a fifth defeat in seven matches for Norrie, who lost in the second round at the Barcelona Open last month following first-round exits at both the Monte-Carlo Masters and Miami Open.