Italian lucky loser Lorenzo Sonego put on a remarkable performance to inflict just the third defeat of the season on world No 1 Novak Djokovic in the quarter-finals of the Erste Bank Open in Vienna.
The 42nd-ranked Sonego lost in qualification but replaced Diego Schwartzman in the main draw after the Argentine pulled out with an injury and he has taken full advantage in the main draw by reaching the final four of the tournament where he will play Britain's Dan Evans.
Sonego produced a sensational performance to dismantle Djokovic 6-2 6-1 and become the first lucky loser to defeat the top seed (1-12) in his career.
The Italian struck 26 winners against a disinterested Djokovic at times, with the Serb making 25 unforced errors.
"For sure it's the best victory of my life," Sonego said in an on-court interview. "I played so, so good today. I like this tournament, I like the conditions here. It's unbelievable."
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Sonego saved all six break points he faced in the match, all coming in second set, while converting five of his six break points for the win of his life.
Before this match, Sonego was 0-3 in his career against top 10 players, but he produced a complete performance on the indoor hardcourt.
Djokovic said: "I came here with the intention to try to earn more points and secure the No 1 in the end of the year. I have done that, so I move on.
"I am happy, I am pleased, I am healthy, and hopefully I can have a strong finish [at the ATP finals] in London.
"I have done what I needed to do and why I came here. I am completely fine with today's result and looking forward to the next chapter."
Djokovic is expected to head off Rafael Nadal and be the year-end No 1 again, but he could have clinched it by winning the Vienna final on Sunday.
Instead, he was looking forward to traveling home to Serbia and not defending his title at the Paris Masters next week.
"I would call it a blessing, being a father and being a husband, its the best thing in the world. I am not far from home, so I look forward to that, he said.
British No 1 Evans came through a tough three-set encounter against resurgent Bulgarian Grigor Dimitrov 7-6 (7-3) 4-6 6-3 after two hours and 43 minutes for his eighth win against top 20 opponents in 2020.
Evans came to the net 47 times, winning 33 points as he reached his second ATP 500 semi-final of the year.
Also, Andrey Rublev reached the semi-finals, continuing his quest for a record fifth ATP title this season.
The Russian beat defending champion Dominic Thiem 7-6 (7-5) 6-2 to set up a date against 2018 champion Kevin Anderson, who defeated Daniil Medvedev 6-4 7-6 (7-5).
"I was lucky that Dominic had problems with the feet," said Rublev. "We had some great battles in the past."
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