Australian Open 2019: Caroline Wozniacki, Angelique Kerber and Sloane Stephens progress
|Australian Open 2019|
|Venue: Melbourne Park Dates: 14-27 January|
|Coverage: Daily live commentaries on the BBC Sport website, listen to Tennis Breakfast daily from 07:00 GMT on BBC Radio 5 live sports extra and watch highlights on BBC TV and online from 19 January.|
Caroline Wozniacki started the defence of her Australian Open title with a 6-3 6-4 victory against Belgian Alison van Uytvanck.
The Dane, who has rheumatoid arthritis, broke her rival once in each set and won in one hour and 33 minutes.
World number two Angelique Kerber also moved into the second round with a 6-2 6-2 win over Slovenia's Polona Hercog.
German 14th seed Julia Gorges, champion in Auckland a week ago, lost 2-6 7-6 (7-5) 6-4 to American Danielle Collins.
- Murray loses five-set epic in possible farewell match
- Federer and Nadal win, Isner loses
- Boulter wins, Watson & Dart out
- Edmund out in first round but Evans wins
Wozniacki's victory in Melbourne last year saw the 28-year-old claim her first Grand Slam title, but she has had physical issues since then and was diagnosed with arthritis in August.
"It's such a special feeling, I love playing back here," she said after her win.
"Last year I had some special memories and just to be able to be back out here on Rod Laver Arena is something extremely special and emotional.
"Now I'm going to start crying and I never cry."
Czech Petra Kvitova, who won the Sydney International title on Saturday, easily beat Slovakia's Magdalena Rybarikova 6-3 6-2.
Fifth seed Sloane Stephens beat fellow American Taylor Townsend 6-4 6-2, while Belarusian 11th seed Aryna Sabalenka cruised through against qualifier Anna Kalinskaya 6-1 6-4.
Sabalenka will face Katie Boulter in the second round after the British number two's stunning victory over Ekaterina Makarova.