SAN FRANCISCO (AFP) - China's Zheng Saisai picked up where she left off at the WTA Tour's Stanford tournament on Monday, by beating Maria Mateas 7-5, 6-1 in a first-round match.
Zheng won the doubles title at Stanford last year, joining forces with compatriot Xu Xifan to beat Anabel Medina Garrigues and Arantxa Parra Santonja 6-1, 6-3.
The 22-year-old has three career WTA doubles titles but is seeking her first singles crown.
She is ranked 74th in the world in singles and 19th in doubles.
Zheng blasted three aces and won 67 per cent of her first serve points in the 85-minute match on the hard courts at Stanford University.
American Mateas recorded seven double faults and struggled with her serve, winning just three points total on her second serve.
In other matches on Monday, France's Alize Cornet beat Jennifer Brady 3-6, 6-4, 6-4 and Nao Hibino of Japan needed three sets as well to down Veronica Cepede 7-5, 4-6, 6-4.
Taking the court in the night session is fifth seeded Misaki Doi of Japan, who faces China's Han Xinyun.