Defending champion Naomi Osaka moved into the last 32 at the Australian Open with a straight-sets win over China’s Saisai Zheng.

The Japanese third seed took one hour 20 minutes to see off the world number 42 6-2 6-4 on Margaret Court Arena.

Osaka, 22, now faces a potential third-round meeting with US teenager Coco Gauff, who plays Sorana Cirstea later.

American 14th seed Sofia Kenin also progressed against compatriot Ann Li, beating the wildcard 6-1 6-3.

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Britons Dan Evans and Heather Watson are looking to progress in the Australian Open on Wednesday after only Harriet Dart survived day two.

Evans, seeded 30th, plays Japan’s Yoshihito Nishioka, with defending champion Novak Djokovic possibly awaiting the winner in the third round.

Watson, ranked 75th, meets Kristyna Pliskova in her first-round match.

The pair were scheduled to meet on Tuesday but the match was postponed because of a backlog.

Evans, 29, is the only Briton left in the men’s singles after Kyle Edmund and Cameron Norrie lost on Tuesday.

The British number one, who fought from two sets down to beat American Mackenzie McDonald on Monday, meets Nishioka second on court 19 at about 02:00 GMT.

Watson, 27, is hoping to join qualifier Dart in the second round after Johanna Konta and Katie Boulter were also beaten on Tuesday.

She opens against Czech world number 64 Pliskova – twin sister of second seed Karolina – on court 12 at 00:00 GMT.

• Dart advances but Konta & Edmund out
• Sharapova ‘unsure’ on future after first-round loss
• Nadal, Kyrgios & Medvedev through to round two

Djokovic is among a star-studded line-up on Rod Laver Arena, taking on Japanese wildcard Tatsuma Ito in his second-round match.

Australian world number one Ashleigh Barty, who is aiming to become the home nation’s first singles champion for 42 years, and Czech 2019 runner-up Petra Kvitova also play in the day session.

American legend Serena Williams continues her quest for a record-equalling 24th Grand Slam singles title by opening the evening session against Slovenia’s Tamara Zidansek, before Swiss great Roger Federer rounds off the night on the 15,000-seat show court, facing Serb Filip Krajinovic.

Nishioka just as tough as Djokovic right now – Evans

Evans is no stranger to playing the biggest names on the biggest stage, having faced Federer at both the Australian Open and US Open last year.

The Briton, playing his first Slam as a seed, will meet 16-time Grand Slam champion Djokovic for the first time in his career if both men win on Wednesday.

First Evans must overcome world number 71 Nishioka, who is looking to reach the last 32 at a major for the first time.

“I have to play Nishioka first and if I do get there it’s a good match, another good opportunity.

“It’s obviously a difficult match but Nishioka’s just as tough right now.

“It’s a good thing to have waiting if I win.”

Evans has lost both of his two previous meetings with the Japanese left-hander, including a 6-4 6-1 defeat at the Washington Open in August.

“If I’m being totally honest I had a real bad mental performance last time,” Evans said.

“It was just before I split with my coach [David Felgate] so I wouldn’t read too much into the last one.”

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Watson hopes new love can inspire change of Grand Slam fortunes

British number two Watson says she is going into the Australian Open feeling “happy on and off the court”, believing her new relationship with Yeovil Town footballer Courtney Duffus has particularly contributed to her improved results.

Watson is hoping to end a miserable run at the Grand Slams – and the Australian Open, in particular – by beating Pliskova.

“He’s super positive. I don’t like boys to have too much influence over me but he has really been a good influence,” a smiling Watson told reporters.

Watson has won only two main-draw Grand Slam matches in the past two years, with just one victory in her past six appearances in the main draw in Melbourne.

Maria Sharapova is not sure if she will be at the Australian Open next year, with a first-round exit meaning she is set to drop out of the world’s top 350.

The five-time Grand Slam champion, who won at Melbourne Park in 2008, lost 6-3 6-4 to Croatian 19th seed Donna Vekic.

It was only the Russian’s second competitive outing since September’s US Open because of a shoulder injury.

Asked whether this might be her last appearance at the tournament, she said: “I don’t know. I don’t know.”

The 32-year-old, who was given a wildcard, added: “I was fortunate to get myself to be here and thanks to [the organisers for] allowing me to be part of this event.

“It’s tough for me to tell what’s going to happen in 12 months’ time.”

This was the former world number one’s earliest exit at the Australian Open since 2010 and she has now gone out in the first round in her past three Grand Slams.

“I put myself out there. As tough as it was, I finished the match and it wasn’t the way that I wanted,” she said.

• Konta, Edmund & Boulter out in first round
• Nadal eases into round two

Halep, Pliskova, Muguruza through to round two

Wimbledon champion Simona Halep had to save three set points in the first set but eventually came through 7-6 (7-5) 6-1 against American Jennifer Brady.

Romanian Halep, who had her right wrist strapped after a fall in the first set, raced through the second set in 27 minutes after the opener took 69 minutes.

World number two Karolina Pliskova raced through the first set before having to work hard in the second as she beat Kristina Mladenovic to reach the second round.

The Czech took the opener in just 25 minutes on her way to a 6-1 7-5 win.

It was a tricky draw for the second seed, with Mladenovic a former top-10 player who helped France win the Fed Cup in November.

Pliskova is unbeaten in 2020, winning the Brisbane International this month.

“We had some good matches in the past and it was tough mentally in the second set,” said Pliskova, who had shared a 2-2 record against Mladenovic before this match.

In the next round, the 27-year-old will play German world number 72 Laura Siegemund.

Pliskova, chasing a first Grand Slam title, is joined in the second round by Swiss sixth seed Belinda Bencic, Dutch ninth seed Kiki Bertens, American 10th seed Madison Keys and Greek 22nd seed Maria Sakkari, but British 12th seed Johanna Konta was knocked out.

Two-time Grand Slam champion Garbine Muguruza fought back from a dreadful first set to beat American Shelby Rogers 0-6 6-1 6-0 and 2016 champion Angelique Kerber of Germany saw off Italian qualifier Elisabetta Cocciaretto 6-2 6-2.

American 26th seed Danielle Collins, a surprise semi-finalist in Melbourne last year, overcame Vitalia Diatchenko 6-1 3-6 6-4.

Czech 15th seed Marketa Vondrousova, a finalist at last year’s French Open, lost 6-2 4-6 6-4 to Russian 34-year-old Svetlana Kuznetsova, while American 18-year-old Amanda Anisimova fell 6-3 4-6 6-3 to Kazakhstan’s Zarina Diyas.

Catherine Bellis, playing at her first Grand Slam in two years, breezed past Germany’s Tatjana Maria 6-0 6-2.

American Bellis, who has fallen to 600 in the rankings, was told she may have to quit tennis after struggling with wrist and elbow injuries.

She had four surgeries in 2018 on her wrist, arm and elbow and only returned to the WTA Tour in November 2019.

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