Paris - US Open champion Sloane Stephens reached her first French Open quarter-final on Sunday, beating Estonia's Anett Kontaveit 6-2, 6-0.
Stephens, the 10th seed, had previously made the fourth round for four successive seasons.
She will face either Australian Open champion and second seed Caroline Wozniacki or Russia's Daria Kasatkina for a place in the semi-finals.
A clearly hobbled Kontaveit hit just five winners but 21 unforced errors in the 52-minute mismatch.
Results from day eight of the French Open at Roland Garros on Sunday (x denotes seeding):
Dominic Thiem (AUT x7) bt Kei Nishikori (JPN x19) 6-2, 6-0, 5-7, 6-4
Alexander Zverev (GER x2) bt Karen Khachanov (RUS) 4-6, 7-6 (7/4), 2-6, 6-3, 6-3
Yulia Putintseva (KAZ) bt Barbora Strycova (CZE x26) 6-4, 6-3
Madison Keys (USA x13) bt Mihaela Buzarnescu (ROM x31) 6-1, 6-4
Sloane Stephens (USA x10) bt Anett Kontaveit (EST x25) 6-2, 6-0