MEMPHIS: Top seed Maria Sharapova continued her march through the WTA Tour event here on Thursday, reaching the semi-finals with a 6-2, 7-5 victory over Britain’s Elena Baltacha.

Meanwhile, American Melanie Oudin fell 6-1, 6-3 to Swedish qualifier Sofia Arvidsson. Sharapova next faces fifth-seeded Czech Petra Kvitova, who beat third-seeded Estonian Kaia Kanepi 1-6, 6-3, 7-6. Arvidsson will face Britain’s Anne Keothavong, a 6-4, 6-3 winner over Croatian Karolina Sprem. In men’s action, top seeded American Andy Roddick booked a quarter-final berth with a 7-6 (7/2), 6-4 victory over Lu Yen-Hsun of Taiwan. Fifth-seeded Czech Tomas Berdych and eighth-seeded Sam Querrey of the United States also reached the quarter-finals.