Wimbledon champion Iga Swiatek became the latest seed to fall at the Canadian Open as she suffered a surprise defeat by Clara Tauson in the fourth round
Denmark's Tauson, ranked 19th, avenged her fourth-round loss to Swiatek at Wimbledon last month with a 7-6 (7-1) 6-3 victory over the second seed in Montreal.
Swiatek's exit comes after top seed Coco Gauff, two-time defending champion Jessica Pegula and fourth seed Mirra Andreeva were all knocked out.
Tauson will face Australian Open champion Madison Keys in the quarter-finals after the American saved two match points en route to a 4-6 6-3 7-5 win over Czech Karolina Muchova.
Earlier on Sunday, four-time major winner Naomi Osaka lost only one game as she outplayed Latvia's Anastasija Sevastova to wrap up a 6-1 6-0 win in 49 minutes.
Japan's Osaka, a winner twice at the US and Australian Opens, is seeking her first title since returning from maternity leave early in 2024.
The 27-year-old parted company with coach Patrick Mouratoglou after less than a year and is now working with Poland's Tomasz Wiktorowski, former coach of Swiatek.
In the men's event, Australian Alex de Minaur continued his fine form with a 6-2 4-6 6-4 win over American seventh seed Frances Tiafoe to reach the quarter-finals in Toronto.
Ninth seed De Minaur, who won the Washington Open a week ago, is looking to go one better than his runners-up spot in 2023.
Denmark's Holger Rune, seeded fifth, suffered a surprise exit as he was beaten 6-4 2-6 3-6 by Alexei Popyrin.