Kerber clobbered American qualifier Irina Falconi of the United States 6-2, 6-3 and moved on to the next round, where she will face another Yank, Melanie Oudin.
Kerber, ranked No. 9 in the world, won 16-of-22 first-serve points and saved 6-of-8 break points compared with 4-of-10 for Falconi, who was born in Ecuador.
Third-seeded Ekaterina Makarova of Russia also advanced with a 6-4, 6-2 win over Canadian Eugenie Bouchard. Fourth-seeded Alize Cornet blew past Yanina Wickmayer 6-1, 6-3. Eighth-seeded Madison Keyes of the United States beat Portugal's Michelle Larcher de Brito 7-5, 6-3.
Sorana Cirstea of Romania, the No. 5 seed, moved on when Lesia Tsurenko of Ukraine retired with Cirstea leading 7-5, 1-1.
Ohio bar shooting arrested, charged with murder
LGBT community has 'bullied the American people': Bachmann