Top seed Agnieszka Radwanska and second seed Angelique Kerber have been the major casualties on the first day at the Madrid tennis Open.

The Australian Open champion Kerber has been beaten 6-4, 6-2 by Czech Barbora Strycova.

Poland's Radwanska has fallen to Dominika Cibulkova in a gritty three set encounter.

A day after beating Kiwi Marina Erakovic in the Rabat final, Swiss star Timea Bacsinszky has beaten German Andrea Petkovic in three sets.