Li Na of China cruised into the fourth round of the Sony Open on Saturday with a straight-set win over American Varvara Lepchenko.

The fifth-seeded Li needed 78 minutes in a 6-2, 6-4 victory. She broke serve four times and had her serve broken just once.

Li, who won the season-opener in Shenzhen before finishing as the runner-up to Victoria Azarenka at the Australian Open, will next face the winner between ninth-seeded Caroline Wozniacki and Spain's Garbine Muguruza.

In addition to the Wozniacki/Muguruza match, seven other third-round battles are on Saturday's schedule.

Top-seeded Serena Williams will meet Japan's Ayumi Morita in the opener of the night session, while Venus Williams will square off against fellow American Sloane Stephens.

Also, fourth-seeded Agnieszka Radwanska will take on Slovakia's Magdalena Rybarikova, seventh-seeded Petra Kvitova will play Kirsten Flipkens of Belgium and Slovakian 13th seed Dominika Cibulkova will tangle with Switzerland's Romina Oprandi.

German Andrea Petkovic is in action against Croatian wild card Ajla Tomljanovic.