Serena Williams continued her tennis comeback 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.

"I'm getting there. I have such a long way to go," the 23-times grand slam champion told reporters.

"It definitely felt better than the first round, but I'm still a little rusty.

"I'm still making errors that I don't normally make. I call this a trial run, of travelling with the baby and all of this is just so new to me."

Venus moved into the third round by beating Romanian Sorana Cirstea 6-3 6-4 in the preceding match.

Monday's meeting will be the earliest between the Williams sisters since their first professional match in the second round of the 1998 Australian Open.

It will be the 29th between the pair, with Serena leading the head-to-head record 17-11.

That record includes a walkover victory for Serena at Indian Wells in 2001, when Venus pulled out minutes before their scheduled semi-final citing a knee injury.

Spectators vented their displeasure with the withdrawal during the final, booing Serena and jeering her sister and father Richard Williams when the pair arrived to watch the match. Richard Williams alleged he had heard racist taunts.

Serena boycotted the event until 2015.

"Obviously I wish it was anybody else in the draw, literally anybody, but that's okay," she said.

"I really abhor every time we play, but I do enjoy the battle when I'm out there. It's just afterwards I don't like it as much."

Venus recovered from a break down in the second set against Cirstea, winning five consecutive games to close it out.

"It takes me a few games, a few matches before hopefully you get it where you want it to be," said the number eight seed after her first match in a month.

"(I was) just trying to work the point, do what it takes to win the point. I haven't played in a long time."

Also moving into the third round was defending champion Elena Vesnina, who beat American Catherine Bellis 2-6 6-1 6-1.

Danish second seed Caroline Wozniacki beat Spaniard Lara Arruabarrena 6-4 6-1, while Ukrainian fourth seed Elina Svitolina defeated German Mona Barthel 6-4 6-3.

Seeds Madison Keys (15), Magdalena Rybarikova (18) and Anett Kontaveit (28) all lost on Saturday.