'So beautiful': Tennis fans erupt over Serena Williams and daughter

Tennis fans are swooning over Serena Williams and her three-year-old daughter, who is in Melbourne watching her mum's quest for a 24th grand slam singles title.

Three-year-old Alexis Olympia has a special connection to the Australian Open after Serena won the 2017 title while pregnant with her.

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Serena has previously revealed that Alexis Olympia's initials (AO) are even a special nod to the Aussie grand slam tournament.

Discussing her daughter after her third round win at Melbourne Park on Friday, Serena said she'd discussed playing doubles with Alexis at the Australian Open one day.

"I've been talking to her about playing doubles here with her one day," Serena told Jelena Dokic during her on-court interview after beating Anastasia Potapova.

"She technically already has an Australian Open title, the trophy's usually in her room.

"But, you know, it was the only thing that we can do social distanced for almost a whole year of COVID is play tennis.

"So I was like 'I would never put my daughter in tennis' and then it's the best socially distanced sport, I think, that you can play."

Serena facing tricky test in fourth round

Serena faces an Australian Open litmus test after shifting into survival mode to make it through the first week at Melbourne Park for a 16th time.

The seven-times champion overcame a shaky start to beat Russian teenager Potapova 7-6 (7-5) 6-2 on Friday.

Up against a player half her age, 39-year-old Williams had to recover from 5-3 down and save two set points in the first set before prevailing over the former Wimbledon junior champion.

Potapova served for the opening set at 5-3 only to cough up two double faults to invite Williams back in.

The 19-year-old then led 5-3 in the tiebreaker before losing four points in a row to concede the set and match momentum.

Potapova took an injury time-out while trailing 4-1 in the second set, but it couldn't stop Williams from advancing after an hour and 37 minutes.

"It definitely feels good to be in the fourth round and it's so good to get through that match," the 10th seed said.

"The first set was extremely tight. I was a little tight, but it worked out. I was able to play a little more free in the second set.

"It's about surviving and playing better every round."

Bidding for a record-equalling 24th grand slam singles crown, Williams will certainly need to be better next round.

The American will take on in-form seventh seed Aryna Sabalenka on Sunday for a quarter-final spot.

Sabalenka has never previously made it past the third round at Melbourne Park and only reached the final 16 once at a grand slam tournament - the US Open in 2018.

But the Belarusian came into the tournament in stellar form and has won 18 of her past 19 matches, including Friday's 6-3 6-1 dispatch of American Ann Li.

with AAP

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