Overview

• Sixth seed Madison Keys was upset by Renata Zarazúa 6-7 (10), 7-6 (3), 7-5 in the first round.
• Venus Williams, 45, made her 25th US Open appearance and lost to No. 11 Karolína Muchová 6-3, 2-6, 6-1.
• Novak Djokovic advanced by defeating 19-year-old Learner Tien 6-1, 7-6 (3), 6-2 after contending with a leg issue.
• The main draw began Sunday under a new 15-day format with a tournament-record $90 million purse and $5 million to each singles champion.
• Players including Jessica Pegula voiced opposition to the Sunday start and scheduling, saying organizers do not heed player concerns.