Andrey Rublev reached the quarterfinals for the first time by beating Marton Fucsovics 6-7 (4), 7-5, 6-4, 7-6 (3).
The 13th-seeded Russian saved three set points serving at 5-4 down and 0-40 in the fourth set.
He won on his second match point when the unseeded Fucsovics put a forehand into the net after Rublev had hit a volley at the net.
The two-time U.S. Open quarterfinalist Rublev had never been beyond the first round at Roland Garros.
Two-time Wimbledon champion Petra Kvitova reached the French Open quarterfinals for the first time in eight years by beating Zhang Shuai 6-2, 6-4.
Kvitova sat waiting wrapped in a pink coat to combat the chilly conditions on Court Philippe Chatrier. She then did some leg exercises to keep warm.
The 30-year-old Kvitova will next face Laura Siegemund. The unseeded German beat Paula Badosa 7-5, 6-2 to reach the quarterfinals at a major tournament for the first time.
There will still be crowds for the final week of French Open after Paris police decided not to reduce the limit of 1,000 spectators per day.
Paris police chief Didier Lallement said bars in Paris will close for two weeks from Tuesday as part of new measures to slow coronavirus infections.
But he maintained the current limit of 1,000 spectators at sports events in Paris and specifically noted the clay-court tournament at Roland Garros.
Many have said how much they appreciate having spectators even in much smaller numbers than normal.
Andrey Rublev, French Open, Márton Fucsovics, Stefanos Tsitsipas, Grigor Dimitrov
Actu monde – AU – French Open 2020, Latest News from Roland Garros: Petra Kvitova Reaches Quarters