Serena Williams struggles on her comeback and now plays sister Venus - in pictures

Serena had to come from behind at the Top Seed Open in Kentucky

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  Serena Williams takes a tumble during her comeback match against Bernarda Pera during the Top Seed Open in Kentucky. AFP

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  Serena Williams' husband and daughter, Alexis Ohanian and Alexis Olympia Ohanian, watch the action. AFP

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  Serena Williams plays a forehand against Bernarda Pera during Top Seed Open in Lexington, Kentucky. AFP

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  Bernarda Pera during her match against Serena Williams. AFP

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  Serena Williams walks across the court. AFP

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  Serena Williams rests between games. AFP

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  Venus Williams plays a backhand during her match against Victoria Azarenka of Belarus. AFP

Serena Williams had to dig deep in an expectedly dramatic return to action in Kentucky.

Williams needed to rally to win on her comeback after a six-month layoff, beating unseeded American Bernarda Pera 4-6, 6-4, 6-1 in the first round of the Top Seed Open.

Williams advanced to a second-round showdown on Thursday against older sister Venus, who dispatched Victoria Azarenka 6-3, 6-2. The two will meet for the 31st time in a match that will be emotionally and physically challenging for both of them.

“From one Grand Slam (winner), one No 1 to another," said Venus Williams, who's record is 12-18 against her sister. “It's been quite the draw for me but, honestly, it's perfect because I don't play forever so I want to play the best players. And I think I got my wish. Here we go.”

Serena first had to clear some athletic hurdles against Pera in the opening match on centre court.

Looking to return to form following the break caused by the coronavirus pandemic, the 23-time Grand Slam champion laboured to avoid her 14th loss to an opponent ranked outside the top 50.

“I just knew I needed to be better,” Williams said. “I knew I could be better. And it was an interesting game. She had so many winners and (was) so low. I just had to kind of get used to a game a little bit. She played really well.”

Williams took 2 hours, 16 minutes to make it to another day at an event where players hope to polish their hard-court skills for this month’s US Open in New York.

Venus Williams had a much easier time against Azarenka on a star-studded Tuesday. The seven-time Slam champion led 4-0 in the second before splitting the final four games to earn her first victory in four attempts this year.

Up-and-coming Coco Gauff, 16, moved on to the next round by beating Caroline Dolehide, 7-5, 7-5.

“I played pretty freely today and it didn't turn out too bad,” said Gauff, who acknowledged some pre-match nerves.

Seventh-seeded Sloane Stephens, the 2017 US Open champion, lost to Canadian qualifier Leylah Fernandez, 6-3, 6-3.