Venus Williams was defeated by Sara Errani in a riveting match, and Angelique Kerber, the No. 6 seed, was dismantled by 17-year-old Belinda Bencic. Simona Halep, the No. 2 seed, also lost.

Former world No. 1 Angelique Kerber has taken her first steps back into tennis as a mentor for Germany’s female players. The 36-year-old will become an advisor to the women’s division of the ...