Agustin Calleri of Argentina downed fourth-seeded Jiri Novak of the Czech Republic, 7-5, 6-1, in a quarterfinal clash between former champions at the Mexican Open tennis tournament in Acapulco, Mexico.

Calleri advanced Thursday to face Albert Montanes of Spain, who eliminated sixth-seeded Filippo Volandri of Italy, 4-6, 6-3, 6-4.  Despite suffering from a stomach virus, Argentine wild card Mariano Puerta beat Felix Mantilla of Spain, 6-4, 3-6, 7-6.  Puerta had upset top-seeded Carlos Moya of Spain one day earlier at the clay court Abierto Mexicano TELCEL event.
In the women's draw, Antonella Serra Zanetti of Italy reached the quarterfinals after topping Emmanuelle Gagliardi of Switzerland, 7-6, 7-5. 

Amilie Mauresmo of France plays Alicia Molik of Australia to highlight early play Friday.

Some information for this report provided by AP.