MADRID (AP) -- Top-ranked Victoria Azarenka and No. 2 Maria Sharapova beat Czech opponents to reach the third round of the Madrid Open on Tuesday.

Azarenka, the defending champion, held off Andrea Hlavackova's challenge to win 6-3, 7-6 (2) after Sharapova beat Klara Zakopalova 6-4, 6-3.

In men's play, Jurgen Melzer rallied past Feliciano Lopez 3-6, 7-6 (6), 6-4, the first seeded player to exit.

Ninth-seeded Gilles Simon of France defeated Fabio Fognini 6-7 (1), 6-3, 6-3. Hard-hitting Canadian player Milos Raonic beat Argentina's David Nalbandian 6-4, 6-4.

Seeded players Juan Martin del Potro, Gael Monfils and Fernando Verdasco also advanced.

Top-ranked Novak Djokovic makes his blue clay debut later Tuesday against Daniel Gimeno-Traver of Spain.

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