Halep makes stunning statement on day of drama

AAP

World No.1 Simona Halep has shrugged off concerns about her injured ankle, breezing into the third round of the Australian Open with a straight-sets win over Eugenie Bouchard.

Halep was in clinical touch on Margaret Court Arena, dispatching the Canadian 6-2 6-2 in one hour and five minutes to set up a date with American Lauren Davis.

BARTY PARTY ROLLS ON: Aussie Ash comes back to win again

The Romanian broke Bouchard's serve seven times and was dominant in the groundstroke battle, winning 44 points at the baseline compared to her opponent's 17.

Halep, who is coached by Australian Darren Cahill, had needed a medical time-out after badly twisting her left ankle during her second-round win over local wildcard Destanee Aiava.

Can Halep break her grand slam duck? Image: Getty

The 26-year-old displayed no ill effects in a dominant performance against former world No.5 Bouchard but admitted afterwards that her ankle was still causing her pain.

The World No.1's crushing victory serves as a huge statement on a day when a number of big guns crashed out.

Sixth-seeded Karolina Pliskova romped into the third round with a 6-1 6-1 dismissal of Brazilian Beatriz Haddad Maia, joining former champion Maria Sharapova, who earlier on Thursday ousted Latvian 14th seed Anastasija Sevastosa 6-1 7-6 (7-4).

Ex-No.1s Sharapova and 2016 Open champion Angelique Kerber - who dispatched Donna Vekic 6-4 6-1 for her 11th straight win of the year - will square off in the first blockbuster of the tournament on Saturday.

Pliskova set up an all-Czech third-round affair with Lucie Safarova, a 6-2 6-4 winner over Romania's Sorana Cirstea.

But third-seeded Wimbledon champion Garbine Muguruza and ninth seed Johanna Konta crashed out of the Open in straight-sets defeats.

Taiwan's Hsieh Su-wei, the world No.88 coached by former Australian Open tournament director Paul McNamee, not only scuppered Muguruza's Open hopes with her shock 7-6 (7-1) 6-4 victory.

Hsieh also dashed Muguruza's immediate prospects of regaining the world No.1 ranking with a Melbourne Park triumph.

A former French Open and Wimbledon doubles champion, Hsieh will meet Agnieszka Radwanska in the next round. Poland's 26th seed progressed with a 2-6 7-5 6-3 win over Belarusian Lesia Tsurenko.

American "lucky loser" Bernarda Pera stunned Konta 6-4 7-5 to continue her dream run after only gaining a last-minute entry to the main draw for the first time following the withdrawal of Russian Margarita Gasparyan.

Pera joins Thai surprise packet Luksika Kumkhum, 15-year-old Ukrainian sensation Marta Kostyuk and Czech Denisa Allertova to advance to the last 32 out of qualifying.

French eighth seed Caroline Garcia narrowly avoided elimination, battling back from a third-set deficit to see off Czech Marketa Vondrousova 6-7 (3-7) 6-2 8-6 in a two-and-half-hour scrap, played out in the searing early-afternoon heat.

The last two American hopes, US Open finalist Madison Keys, and Lauren Davis also both won.

Unseeded Sharapova, in her return to Melbourne after missing last year's event during a doping ban, Kerber and French Open champion Jelena Ostapenko are the only grand slam winners left in the draw.

And with veteran Croat Mirjana Lucic-Baroni, the 28th seed, succumbing 6-3 6-1 to Belarusian Aliaksandra Sasnovich, not one of last year's four women's semi-finalist remain.

Serena Williams was unable to defend her crown following the birth of her first child in September, while her sister Venus and fellow American CoCo Vandeweghe both bombed out in round one.