Paris - World No 1 Simona Halep, the runner-up in 2014 and 2017, routed Belgian 16th seed Elise Mertens 6-2, 6-1 to reach the French Open quarter-finals for the third time on Monday.
Top seed Halep will take on either German 12th seed Angelique Kerber or Caroline Garcia, the seventh-seeded Frenchwoman who made the last-eight in 2017.
Halep won in 59 minutes with the second set taking just 22 minutes.
The Romanian broke serve six times against a player who made the semi-finals at the Australian Open in January.
Results from day nine of the French Open at Roland Garros on Monday (x denotes seeding):
Simona Halep (ROM x1) bt Elise Mertens (BEL x16) 6-2, 6-1
Daria Kasatkina (RUS x14) bt Caroline Wozniacki (DEN x2) 7-6 (7/5), 6-3