The world premiere, Aryna Sabalenka, moved into the Miami Open in the last 16 times after the opponent Elena-Gabriela Ruse retired, while there were victories for Naomi Osaka and Coco Gauff.
Sabalenka had taken the first 6-1 set before Romanian Ruse retired with a thigh problem in the first match of the second.
Osaka in Japan survived a fear to finally overcome the American Joker Hailey Baptiste in a match of almost three hours.
The world’s number 98 Baptist was a breakup and served 4-3 in the third decisive set, but Osaka returned well.
The quadruple Grand Chelem champion held the service before breaking Baptiste again to take the 7-6 match (8-6) 3-6 6-4 in two hours, 59 minutes and 57 seconds-the longest female match of the tournament so far.
