Maria Sharapova and Venus Williams moved into the second round at the China Open with straight-set victories.
The fourth-seeded Sharapova overcame six double-faults to defeat Estonian Kaia Kanepi 6-4, 6-1, while the 16th-seeded Williams came back from a 3-0 deficit in the opening set to defeat Britain's Heather Watson 6-3, 6-1.
Sharapova, the reigning French Open champion, said despite the double-faults she thought she served well against the 46th-ranked Kanepi, a five-time Grand Slam quarterfinalist.
"I thought I played a difficult opponent, someone that I've had trouble against in the past,'' she said.
"I'm usually somebody that goes for my serve. If I make more errors, I feel more confident knowing that I'm going for it rather than just making my opponent hit a ball.''
Williams, who recently returned to the top 20 in the rankings for the first time in over a year, could next face France's Caroline Garcia, who beat her in three tight sets at the Wuhan Open last week.
Garcia plays China's Zhang Shuai in the first round.
In other first-round matches on the women's side, Australian Samantha Stosur beat Francesca Schiavone of Italy 6-4, 6-2 to set up a second-round clash with the in-form Caroline Wozniacki, who reached the finals of the US Open earlier this month.
Other winners included Ekaterina Makarova of Russia, who beat Spain's Garbine Muguruza 6-7, 6-4, 6-4, and Andrea
Petkovic of Germany, who took out Romanian qualifier Monica Niculescu 2-6, 7-6, 6-4.
15-Andrea Petkovic (Germany) beat Monica Niculescu (Romania) 2-6, 7-6, 6-4
4-Maria Sharapova (Russia) beat Kaia Kanepi (Estonia) 6-4, 6-1
16-Venus Williams (US) beat Heather Watson (Britain) 6-3, 6-1
12-Ekaterina Makarova (Russia) beat Garbine Muguruza Blanco (Spain) 6-7, 6-4, 6-4
Roberta Vinci (Italy) beat Yaroslava Shvedova (Kazakhstan) 6-2, 2-6, 6-1
Samantha Stosur (Australia) beat Francesca Schiavone (Italy) 6-4, 6-2