Paris (AFP) - Australia's Alex de Minaur sent former world number one Daniil Medvedev crashing out of the Paris Masters on Wednesday, rediscovering his momentum in the final set to win 6-4, 2-6, 7-5.
Earlier, fifth-ranked Stefanos Tsitsipas had no problem in seeing off Britain's Dan Evans 6-3, 6-4 to book his place in the last 16.
De Minaur rallied from 0-2 in a topsy-turvy final set but squandered two match points on the Russian's serve in a gripping 10th game.
Despite that disappointment, he was again aggressive on return at 6-5 and a Medvedev double fault on a fourth match point at 30/40 gave De Minaur the biggest win of his career.
The world number 25, who had not previously beaten a top-five player, will now face US Open semi-finalist Frances Tiafoe, who eased past Jack Draper 6-3, 7-5.
After dropping the opening set, third-ranked Medvedev appeared to be back in control as he romped through the second set to level the match.
But the Russian became increasingly agitated, losing confidence, especially on his serve, and delivered a string of unforced errors.
He let out his frustration at the end of the match, which lasted two hours and 46 minutes, smashing his racket on the ground before warmly congratulating his 23-year-old opponent.
Greek star Tsitsipas had the edge over Evans from the start and completed a comfortable victory in 80 minutes.
With Evans struggling to get into the contest and committing a number of unforced errors, Tsitsipas took the initiative by breaking his opponent's opening service game in both sets.
"I was really looking forward to going out there and playing a proper match," said Tsitsipas.
"Not great memories from last year but I was trying to give it another go this year.I'm happy with the way I played, I'm happy with the level of tennis I brought when I had to and it was a great start."
The 24-year-old, whose best performance at Bercy came in 2019 when he lost to Novak Djokovic in the quarter-finals, will face either Cameron Norrie, another Briton, or Frenchman Corentin Moutet in the last 16.
Both he and Medvedev were guaranteed to play the end-of-season ATP Finals in Turin later this month regardless of their performance in Paris.
Italy's Lorenzo Musetti beat Nikoloz Basilashvili of Georgia 6-4, 6-2 to set up a last-16 meeting with third seed Casper Ruud.