Sixth-seeded Angelique Kerber moved on easily at the U.S. Open to set up a second-round match with Venus Williams.
The German beat Britain's Anne Keothavong 6-2, 6-0 in 54 minutes Tuesday. Keothavong, ranked 81st, had 25 unforced errors to Kerber's nine.
Ranked outside the top 100 at the start of 2010, Kerber is now a career-best sixth. She reached her first Grand Slam semifinal at Flushing Meadows last year.
Williams is unseeded at No. 46 in the world after missing time because of illness, and Kerber was the top player who drew her early in the tournament.