Heather Watson made a first-round exit at the BNP Paribas Open in Indian Wells after going down 6-4 6-2 to former world No 1 Victoria Azarenka on Thursday.
The Belarusian, playing her first WTA Tour match in eight months because she will not leave California due to an ongoing custody battle over her son, broke five times to Watson's two to book a second-round meeting with US Open champion Sloane Stephens.
The match was Azarenka's first since Wimbledon last year, with the custody battle seeing her pull out of both the US and Australian Opens.
Azarenka is currently unable to take the one-year-old out of California and has not been prepared to travel without him.
The 28-year-old started as if she had never been away, racing into a 5-1 lead before the Briton cancelled out her opponent's two breaks to get the match back on serve at 5-4. The Belarusian broke straight back though to take the set.
She broke for a 2-0 lead at the start of the second and saved seven break points at 4-2 up on her way to closing out the match.
Azarenka held back tears as she walked out on court and, after winning the match, she told reporters about her struggles.
"I wouldn't wish that on anybody to go through what I've been going through, but it's part of life and there are blessings in this situation as well for me," said the 28-year-old.
"I'm free but it's definitely been and still is a really difficult situation to be in and it's hard to only focus on playing tennis. One day I'll write a book about this, because it's Hollywood-worthy for sure. But right now I just want to keep it a little bit private.
"It's unfortunate and it's not a great time but it's part of life and I'm still 28 years old and recently there are number ones over 30 so I'm okay with that. I'm still young."
You can watch the ATP Masters 1000 from Indian Wells with coverage getting underway from 7pm on Sky Sports Action and via the red button on the same channel on Friday & then on Sky Sports Arena this weekend.
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