Serena Williams won her second match since returning from a 14-month absence to set up a third-round encounter with her sister Venus in Indian Wells.
Two-time champion Serena beat Dutch 29th seed Kiki Bertens 7-6(5) 7-5.
“She started out really strong and I thought I’ve just got to keep going and doing the best I can,” said the American.
“I’m just so happy to be out here, everything is a bonus.”
— WTA (@WTA) March 11, 2018
Serena is playing her first competitive singles event since winning the 2017 Australian Open, since when she gave birth to her daughter Alexis Olympia in September.
“I call this a trial run, of travelling with the baby – all of this is just so new to me,” she added.
She now faces a 29th career meeting with her elder sister in round three after Venus earlier beat Romania’s Sorana Cirstea 6-3 6-4.
“Obviously I wish it was anybody else in the draw, literally anybody, but that’s okay,” said Serena. “I just have to go out there and see how I am and do my best.”
Rain meant that Victoria Azarenka’s comeback was interrupted, with her second-round match against US Open champion Sloane Stephens now scheduled second on Stadium 2 on Sunday.
Serena Williams returned to action on Thursday with a straight-sets win over Zarina Diyas, and followed up by coming through a tough examination from Bertens.
The pair had met twice before, the last time in the 2016 French Open semifinals, and on both occasions Williams had needed a tie-break before winning in straight sets.
It was the same story in Indian Wells as the 23-time Grand Slam champion, who admitted she was “rusty” in round one, twice came back from a break down in the opening set.
Bertens served for it at 5-4 but could not stave off three break points, and the Dutch player must have felt a sense of the inevitable when it came down to a tie-break.
Williams screamed with delight as she moved 6-3 clear, converting her third set point and then breaking early in the second.
Bertens would not crumble, twice recovering breaks of serve – the second as Williams served for the match at 5-4 – and earning two break points in game 12 for another tie-break.
The American was not to be denied, however, recovering from 15-40 down to set up a first match point, only to double fault, before Bertens finally succumbed on the second.
Australian Open champion Caroline Wozniacki was one of several leading names to make progress on the women’s side, the Dane seeing off Spain’s Lara Arruabarrena 6-4 6-1.
“I feel like I have nothing to prove to anyone or to myself anymore,” said Wozniacki, who plays Belarusian Aliaksandra Sasnovich in the third round.
— WTA (@WTA) March 11, 2018
“I can just go out there and enjoy it. But it doesn’t feel different at all in the way that, when you’re out there on court, it’s just a grind.
“Nobody gives you anything. You just have that target back on your back. You just have to try and play your best every single time.”
Tenth seed Angelique Kerber trailed Ekaterina Makarova 6-3 but held a break point at the start of the second set when rain suspended play.
Earlier, fourth seed Elena Svitolina, seventh seed Caroline Garcia and 20th seed Daria Kasatkina made smooth progress.
And after a flurry of teenage winners on Friday, 18-year-old Russian Sofya Zhuk also made round three as she beat 18th seed Magdalena Rybarikova 6-3 2-6 7-5 after converting her 12th match point.
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