'Learned a lot': Naomi Osaka's bold admission after difficult year

Naomi Osaka has shaken off any signs of rust in her second match since arriving in Australia, thumping world No.82 Maryna Zanevska in straight sets at the Melbourne Summer Set.

After taking three sets to topple France's Alize Cornet in the first round of the Melbourne warm-up tournament, Osaka looked comfortable in her second match since a third-round exit from the US Open last September.

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Clearly rejuvenated upon her return to Australia, Osaka said she had learned a lot about herself after taking time away from the sport.

Her US Open exit followed her shock withdrawal from the French Open last year, with Osaka admitting the pressure of being the face of the 2021 Tokyo Olympics had also weighed heavily on her.

Osaka's decision to withdraw from the French Open was centred around her reluctance to honour media commitments in the lead-up to the slam.

After her 6-1, 6-1 win over Zanevska, Osaka said it was a 'breath of fresh air' to be back in Melbourne for the Australian Open and that she was feeling very relaxed on court.

"I learned a lot from my match before today, so I'm really glad that I was able to apply it," she said of her improvement.

"It's definitely nice to have that feeling of learning throughout the tournament.

"My opponent, I felt like she was a sweetheart.

"It was just nice to be able to share a moment. I think we both laughed when the person behind us coughed directly when she was about to serve.

"(The match) was fun."

Osaka will play German veteran Andrea Petkovic in the quarter-final, with former world No.1 Simona Halep lurking in the bottom half of the draw.

"I respect them ... I don't think it's anything to be taken lightly," she said of Petkovic's longevity.

"They've been here for a long time for a reason ... there's just something cool about playing someone that you've watched on TV multiple times."

Angelique Kerber delays Open arrival after infection

Former champion Angelique Kerber will contest the Australian Open without having had any match practice after a positive coronavirus test forced a delay to her departure to the season's first grand slam.

Germany's 2016 winner will miss a potential tune-up tournament in Sydney and travel only on Friday direct to Melbourne, where the Australian Open begins on January 17.

"I'm disappointed that I will miss the WTA event in Sydney but after I tested positive for COVID-19 last month, I had to adjust my plan due to the quarantine time," the 33-year-old said on Thursday on social media.

Kerber also had a difficult trip to last year's Open as she had to spend two weeks in quarantine before the tournament, having been a close contact to an infected person on her plane. She was then knocked out in the first round.

"I've done my medical check ad I hope that I'll be ready for the Australian Open," said Kerber, the world No.16 who will travel without a coach having split from Torben Beltz at the end of last season.

Japanese favourite Kei Nishikori has also withdrawn because he's still recovering from a hip injury.

Nishikori, who reached a career-high ranking of fourth shortly after becoming the first man from Asia to reach a major final at the 2014 US Open, has been plagued by injuries in recent years and struggled for consistency.

"Since the end of last year I have been struggling with my hip," Nishikori, currently ranked 47th, said on Twitter on Thursday.

"It is not 100% recovered yet and I will have to pull out of the Aussie swing.

"This is very disappointing as the Australian Open feels like my "home" grand slam... And can't wait to be back next year."

The 32-year-old suffered a first-round exit in last year's edition of the Melbourne Park major, which begins on January 17.

With AAP

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