Simona Halep two-time champion defeat Coco Gauff 6-4, 7-6 (2) to secure her place in the National Bank Open semifinals.
Halep, the 30-year-old from Romania, finish first in the event in Montreal in 2016 and 2018. She will face seventh-seeded Jessica Pegula, a 6-3, 6-3 winner over Yulia Putintseva of Kazakhstan.
The 15th-seeded Halep is 4-0 against the Gauff, the 18-year-old American seeded 10th.
However, in the night session, Beatriz Haddad Maia of Brazil ousted 12th-seed Belinda Bencic of Switzerland 2-6, 6-3, 6-3. On Thursday, Haddad Maia crushes top-tier Iga Swiatek of Poland.
In the late match, 14th-seeded Karolina Pliskova of the Czech Republic played Zheng Qinwen of China.