Rankings twist hanging over Barty’s AO assault

There will be an Australian in the enemy camp tonight as Ash Barty meets American upstart Amanda Anisimova in the fourth round and the Aussie star’s world No.1 ranking is starting to come under threat.

Anisimova has enlisted top Aussie coach Darren Cahill as a member of her team and the results speak for themselves after the 60th-ranked 20-year-old stunned defending champion Naomi Osaka in the third round.

Speaking on Wide World of Sport’s The Morning Serve Sam Groth said Cahill – also working as a Nine analyst in Melbourne – was more of an advisor/mentor than a hands-on coach but his presence was undoubtedly a fillip for Anisimova.

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“He’s not necessarily coming in trying to change everything and I think that’s what Darren does well,” Groth said.

“Just give that little 5-10 per cent more… I think it’s a danger match (for Barty) for sure.

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“I had Ash playing Osaka in the fourth round, like we all did. She’s just gone and knocked out the defending champion – Anisimova is certainly one for the future.

“She’s doing a lot of things right, she’s won a title this year and has confidence after knocking out Osaka. But Barty has been near perfect.”

But despite Barty being in career best form, she is not assured of retaining her world No.1 status at the end of the tournament.

Second seed Aryna Sabalenka, who advanced 4-6, 6-3, 6-1 over No.31 Marketa Vondrousova yesterday, remains a contender.

The 23-year-old from Belarus can potentially overtake Barty depending on results – despite her incredibly shaky serve.

Sabalenka made 19 double faults in her second round win but improved that glaring statistic against Vondrousova.

“I’m really happy right now,” Sabalenka said, laughing, in her on court TV interview.

“Mostly I’m happy I made only 10 double faults.”

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