Cheers and tears in women's day four action

Caroline Wozniacki showed the form that took her to the top of women's tennis with a resounding second round win against Donna Vekic at the Australian Open.

The former world number one put on a returning masterclass to beat the Croatian in straight sets, 6-1, 6-3.

The Dane has only conceded seven games in her opening two matches and will play red-hot Brit Johanna Konta in the next round.

The British No.9 seed continued her love affair with the Australian Open by downing Japan's Naomi Osaka in the second round.

Having reached the semis on her main-draw debut at Melbourne Park last year, Konta eased into the round of 32 with a 6-4 6-2 win over the hard-hitting Osaka.

"If I continue to keep my priorities straight, really take care of the work, take care of my body, then I will continuously be able to have the opportunity to improve, to get better, to experience more matches, to experience more situations," said the 25-year-old Konta.

"In turn, a lot of it is time.

"Also I don't know what it is about fate or being in the right place at the right time.

"But I think some things need to come together, and I love what I do, so hopefully I'll be around for many more years with my body staying healthy."

Sara Errani broke down in tears during her second round match against Russian Ekaterina Makarova.

The Italian was forced to retire through injury at 3-2 down in the second set after the Russian had taken the opener.

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