Azarenka moved on to the second round with a 7-6 (7-5), 6-4 triumph over Svetlana Kuznetsova, despite 10 aces fired by the Russian.
Meanwhile, second-ranked Sharapova -- fresh from her win over Azarenka last week in Stuttgart, Germany -- breezed past Irina-Camelia Begu 6-0, 6-3 in a match that last just more than an hour, saving three break points en route to the win.
Also advancing Sunday was No. 4 seed Agnieszka Radwanska of Poland, who bested Lara Arruabarrena-Vecino 6-3, 6-1 on the clay courts of The Magic Box in Madrid.
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