Novak Djokovic racked up his 35th win of 2020 and a place in the Roland Garros quarter-finals for the 14th time with a 6-4, 6-3, 6-3 win over Russia's Karen Khachanov on Monday.
The world number one, chasing a second title in Paris and 18th career Grand Slam, goes on to face either Spain's Pablo Carreno Busta or unseeded Daniel Altmaier of Germany for a place in the semi-finals.
Djokovic, who hit 44 winners, has yet to drop a set in the tournament, losing just 25 games in four rounds.
"It was a tight match and I am happy to win in straight sets," said the world number one who has now reached 47 quarter-finals at the Slams. It will also be his 11th in a row in Paris.
He had a heart-stopping moment in the first set when he stretched for a forehand and was unable to avoid seeing the ball accidentally hit a line judge.
The incident came just weeks after he was defaulted at the US Open for swiping at a ball which felled a line judge standing behind him.
French Open results at Roland Garros on Monday, the ninth day of the delayed 2020 championship (x denotes seeded player):
Novak Djokovic (SRB x1) bt Karen Khachanov (RUS x15) 6-4, 6-3, 6-3
Andrey Rublev (RUS x13) bt Marton Fucsovics (HUN) 6-7 (4/7), 7-5, 6-4, 7-6 (7/3)
Stefanos Tsitsipas (GRE x5) bt Grigor Dimitrov (BUL x18) 6-3, 7-6 (11/9), 6-2
Petra Kvitova (CZE x7) bt Zhang Shuai (CHN) 6-2, 6-4
Laura Siegemund (GER) bt Paula Badosa (ESP) 7-5, 6-2