MADRID, Spain -- Top-seeded Chanda Rubin struggled in the first set before beating Ivana Lisjak of Croatia 7-6 (5), 6-1 Wednesday at the $170,000 Spanish Open.

Rubin is ranked eighth in the world but had early trouble against an opponent not in the top 300. Lisjak was up 5-4 in the first set but her game quickly fell apart.

Rubin advances to the quarterfinals against fifth-seeded Paola Suarez of Argentina. Suarez defeated Fabiola Zuluaga of Colombia 6-3, 7-6 (2) in this clay-court tuneup for the French Open, which starts Monday.