Cincinnati Masters quarterfinals on Thursday while women's world number one Iga Swiatek was upset by American Madison Keys. Top seed Medvedvev kept Denis Shapovalov winless against world number ones with a 7-5, 7-5 victory while Poland's Swiatek lost 6-3, 6-4 to 2019 Cincinnati champion Keys, who needed five match points to finish off the shock triumph.
Shapovalov, who lost in an hour and three-quarters, has dropped all eight career matches he has played against the elite echelon.
Medvedev moved into a quarter-final against 11th seed Taylor Fritz after the American stopped number six seed Andrey Rublev 6-7 (4/7), 6-2, 7-5. "It was a fight today, definitely not easy," said Medvedev, who clinched the top US Open seeding when Rafael Nadal lost here in the second round. "The match was pretty tight, played at a great level.
My goal was to stay in every point possible and try to put pressure on him if I had the chance." Medvedev secured late breaks in both sets as he matched his volatile Canadian opponent.