Simona Halep and Kaia Kanepi are level at one win apiece in previous meetings, as the pair meet in the first round for the second consecutive Grand Slam. Kanepi's shock victory at Flushing Meadows last summer came after Halep won the first meeting of the duo, in Doha four years earlier.
Eugenie Bouchard aims to maintain her winning run over Shuai Peng, having prevailed at Indian Wells in 2014 and the Australian Open two years ago - both in straight sets.
Johanna Konta and Ajla Tomljanovic clash for the third time - with the other two meetings also taking place in Australia. The Brit won their first meeting, in Brisbane last year, while Tomljanovic gained revenge at the same venue earlier this year.
Shuai Zhang faces Dominika Cibulkova for the sixth time, still awaiting her first victory. The Slovakian won the pair's Fed Cup opener in 2010 and again prevailed at the US Open and Beijing the following year before further victories in Acapulco in 2014 and Brisbane three years later.
Serena Williams begins her first Australian Open campaign in two years as one of five former champions in the draw. The seven-time winner is joined by Maria Sharapova, Victoria Azarenka, Caroline Wozniacki and Angelique Kerber.
Venus Williams makes her 81st Grand Slam appearance, extending her own record. The American moves 10 clear of Amy Frazier, with sister Serena one further back on 70. Francesca Schiavone sits on 69, with Martina Navratilova on 67.
Alizé Cornet begins her 49th consecutive Grand Slam, the longest current unbroken streak. Ekaterina Makarova has played in 46 on the spin, two more than Anastasia Pavlyuchenkova and three more than Julia Goerges. Japan's Ai Sugiyama holds the record, with 62 Slams on the trot.
Whitney Osuigwe, 16, begins her campaign as the youngest player in the draw - the American wildcard one of seven teenagers taking part in Melbourne this year.
ORDER OF PLAY
Five to watch in this year's draw by The Guardian's Jacob Steinberg
Ashleigh Barty ready to embrace the pressure by Scott Bailey & Greg Baum of the Sydney Morning Herald
Can Sabalenka ride her hot streak all the way to the title? asks Ravi Ubha of the New York Times