Sharapova powered past Misaki Doi in 47 minutes -- 8 minutes quicker than her first-round double-bagel win over Olga Puchkova. Sharapova is the first woman to win consecutive Grand Slam matches without dropping a game since Wendy Turnbull in the 1985 Australian Open.
Sharapova dropped just 15 points overall Wednesday and won 26-of-31 (77 percent) of the points on serve.
Fourth-seeded Agnieszka Radwanska ran her 2013 record to 11-0 -- all in straight sets -- with a 6-3, 6-3 win over Irina-Camelia Begu. She had 14 unforced errors against 38 for Begu and converted half of her 12 break-point chances.
No. 5-seeded Angelique Kerber won 6-3, 6-1 over Lucie Hradecka by winning 58 percent of the points when receiving serve and finishing off six break chances. Li Na, the sixth seed, beat Olga Govortsova 6-2, 7-5, taking more than 60 percent of the points on serve and losing her serve only twice.
Other upsets Wednesday saw Valeria Savinykh edge past No. 15 Dominika Cibulkova 7-6 (8-6), 6-4; Kirsten Flipkens defeat 23rd-seeded Klara Zakopalova 6-1, 6-0; and Madison Keys eliminate No. 30 Tamira Paszek 6-2, 6-1.