(Reuters) - Serena Williams continued her comeback to tennis with a 7-6(5) 7-5 win over Kiki Bertens at the BNP Paribas Open on Saturday, setting up a third-round encounter with her sister Venus.
Serena, who is returning to the sport after taking more than a year away to have a baby, was ragged at times but used her power to wear down the Dutch 29th seed in Indian Wells, California.
"She started out really strong," said 23-times grand slam champion Serena in a courtside interview. "I was (thinking) I've just got to keep going and do the best I can.
"I'm just happy to be out here. Everything is a bonus."
Venus moved into the third round by beating Romanian Sorana Cirstea 6-3 6-4 in the preceding match.
It will be the earliest meeting between the two since their first professional match in the second round of the 1998 Australian Open. Monday's match will be the 29th between the pair, with Serena leading the head-to-head record 17-11.
Venus said it looked like her sister had never been away.
"She looked like she never lost a step," Venus said.
Also moving into the third round was defending champion Elena Vesnina, who beat American Catherine Bellis 2-6 6-1 6-1.
Danielle Collins beat fellow American and 15th seed Madison Keys 6-3 7-6(1), Slovak 18th seed Magdalena Rybarikova fell to Russian teenager Sofya Zhuk 6-3 2-6 7-5, while Estonian 28th seed Anett Kontaveit lost to Aliaksandra Sasnovich of Belarus 6-2 6-4.
Ukrainian fourth seed Elina Svitolina avoided a similar demise, beating German Mona Barthel 6-4 6-3.
(Reporting by Andrew Both in Cary, North Carolina; Editing by Peter Rutherford)