World number one Iga Swiatek reached the Qatar Open quarter-finals for a third successive year on Wednesday as fellow four-time Grand Slam champion Naomi Osaka also made the last eight without hitting a ball. Swiatek, the two-time defending champion at the Gulf event, defeated 14th seed Ekaterina Alexandrova 6-1, 6-4. The Russian battled bravely, saving four match points in the 10th game of the second set before Swiatek came through. The 22-year-old Pole will face another two-time Doha champion, Victoria Azarenka, in Thursday's quarter-finals. Former world number one Azarenka beat eighth-seeded Jelena Ostapenko 6-0, 6-3 for her third win over the Latvian this year.