MADRID (AP) — Top-seeded Agnieszka Radwanska and Australian Open champion Angelique Kerber were upset in the opening round of the Madrid Masters on Sunday.
Radwanska, who was elevated to the No. 1 seeding when Serena Williams withdrew, was beaten 4-6, 7-6 (3), 3-6 by Dominika Cibulkova of Slovakia.
Radwanska hit five aces but also had six double-faults and was broken 11 times by Cibulkova.
Barbora Strycova of the Czech Republic beat second-seeded Kerber 6-4, 6-2.
Cibulkova was coming off a win at the Katowice Open last month and a narrow loss to Radwanska at Indian Wells, where she had a match point.
Cibulkova will next meet Caroline Garcia, who was leading 6-4, 2-1 when Johanna Konta retired from their match.
Heading into their clay-court opener, Kerber hadn’t dropped a single set to Strycova in four prior meetings.
But the third-ranked Kerber was broken by Strycova four times to fall in a little over an hour.
The 33rd-ranked Strycova faces Madison Keys, who rallied past fellow…