American Taylor Fritz upset two-time defending champion Stefanos Tsitsipas 6-2, 6-4 to reach the Monte Carlo Masters semifinals Friday.
Second-seeded Tsitsipas was on a 12-match winning streak on the French Cote d’Azur, where he claimed his two Masters 1000 titles.
“I stuck to the strategy of pulling the trigger and not letting him dictate with his forehand,” the No. 8 seed Fritz said.
Tsitsipas broke back to 4-4 in the second set, but Fritz broke his serve easily for 5-4 and closed out the match with an ace for a love hold to reach the semifinals of a Masters event for the first time.
“I just seemed off. My serve was not working very well today, and against opponents like Taylor, you have to serve well,” Tsitsipas said. “I was aware of that during the match. I just couldn’t find the rhythm. I am much better than this, and I’m disappointed I was not able to show my game today.”
The top two seeds have now been knocked out of the clay-court tournament following Novak Djokovic‘s exit in the third round Thursday.
Fritz will next face fifth-seeded Andrey Rublev of Russia, who beat German qualifier Jan-Lennard Struff 6-1, 7-6 (5).
In the other half of the draw, Denmark’s Holger Rune tormented No. 3 seed Daniil Medvedev with passing shots and drop shots to advance with a 6-3, 6-4 victory.
The 19-year-old Rune, who proved a sensation at last year’s French Open when he reached the quarterfinals, dropped only six points on serve in the opening set and converted his only break chance in the second.
He will next meet Jannik Sinner, who defeated Lorenzo Musetti 6-2, 6-2 in an all-Italian quarterfinal.
The Associated Press and Reuters contributed to this report.