Local boy Andrey Rublev was sensationally knocked out of his hometown tournament, the Kremlin Cup, by Adrian Mannarino on Thursday.
Frenchman Mannarino, 33, lost the first set but rallied to win 5-7, 7-6 (7-4), 6-3 in a shade under two-and-a -half hours.
Mannarino will next play Lithuanian Ricardas Berankis in the quarter-finals.
Berankis won easily over Argentina’s Federico Coria 6-2, 6-1.
No.4 seed Filip Krajinovic is also out beaten 6-3, 6-4 by Spaniard Pedro Martinez.
Martinez will now meet Marin Cilic.
Aslan Karatsev beat Egor Gerasimov, of Belarus, 6-4, 6-3 to become the second Russian to reach the last eight.
Karen Khachanov is the other, and he meets Australia’s John Millman next.