Japan's Nara moved on with a 6-0, 7-6 (7-3) decision over German Anna-Lena Friedsam on the clay courts of the Jockey Club Brasileiro.
Her next opponent will be Spain's Dominguez Lino, who rallied past South African Chanelle Scheepers 2-6, 7-6 (9-7), 6-1 Thursday.
In other second-round action, Romanian Irina-Camelia Begu bested Paraguayan Veronica Cepede Royg 6-3, 5-7, 6-1, and Brazilian crowd favorite Teliana Pereira downed Austria's Patricia Mayr-Achleitner 6-2, 7-6 (7-5).
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