A winner of 21 grand slam singles titles, top seed Williams could barely have been presented with a more perilous path as she she seeks to defend her title. Indeed, just to make the semi-finals Williams may need to beat close friend and former world No.1 Caroline Wozniacki in the round of 16, before a looming quarter-final rematch of last year's decider against fifth seed Maria Sharapova, against whom Williams has admittedly won 17 consecutive matches.

If not Sharapova, Williams could face rising Swiss teenager Belinda Bencic, or dual grand slam title winner Svetlana Kuznetsova in the last eight. Williams, 34, wasn't even spared in the first round, forced to confront Italy's Camila Giorgi, the highest-ranked non-seed in the women's draw.

Stosur, the lone Australian woman seed (25), is in the same half of the draw as Williams, and faces a similarly difficult road to achieving a career-best result in Melbourne. While the veteran will face a qualifier in the opening round, she will then likely have to topple in-form Puerto Rican Monica Puig, who on Friday progressed to the final of the Sydney international, defeating Bencic after the youngster retired following a 6-0 first set pummelling. Worryingly for Stosur, Puig had only reached that stage of the Open lead-up event after downing the Australian in straight sets on Wednesday. Should the 2011 US Open winner make it to the last 32, she faces a potential date with fourth-seeded Pole Agnieszka Radwanska or former Wimbledon finalist Eugenie Bouchard, who is on the comeback trail from a concussion sustained last year at Flushing Meadows.

Elsewhere in the women's draw, second seed Simona Halep was placed in the same quarter as eighth seed Venus Williams, while Australian teenage wildcard Kimberly Birrell landed a first-round meeting with ninth seed Karolina Pliskova of the Czech Republic.

While the major talking point in the men's draw was Lleyton Hewitt's impending clash with James Duckworth, Australian seeds Nick Kyrgios and Bernard Tomic will need to overcome highly fancied opponents to make it to the last eight.

Tomic, seeded 16, meets Uzbekistan's Denis Istomin in the first round, but is due to play second seed Andy Murray should both men make it to the fourth round. Firebrand Kyrgios, the 29th seed, faces Spain's Pablo Carreno Busta to begin his Open, but could face sixth-seeded Czech Tomas Berdych in the last 32.

Other features of the first round include matches between former finalists Jo-Wilfried Tsonga and Marcos Baghdatis, and a rematch of the epic 2009 semi-final between Spaniards Rafael Nadal and Fernando Verdasco. Nadal, seeded fifth, will meet his conqueror from the 2014 final - Stan Wawrinka - if both men make it to the quarter-final stage.

John Newcombe medallist Sam Groth starts his campaign against Frenchman Adrian Mannarino, but faces a stiff task to make it to the third round given his second opponent will probably be Murray. World No.1 and defending champion Novak Djokovic meets Korean Hyeon Chun in the first round, while third seed Roger Federer has been pitted against Georgian Nikoloz Basilashvili.

AUSTRALIANS IN FIRST ROUND:

Men:

Omar Jasika v Ilya Marchenko (UKR)

29-Nick Kyrgios v Pablo Carreno Busta (ESP)

Lleyton Hewitt v James Duckworth

Thomaz Bellucci (BRA) v Jordan Thompson

Matthew Ebden v Marcel Granollers (ESP)

16-Bernard Tomic v Denis Istomin (UZB)

John Millman v Diego Schwartzman (ARG)

Adrian Mannarino (FRA) v Sam Groth

Women:

Ajla Tomljanovic v Kateryna Bondarenko (UKR)

Daria Gavrilova v Lucie Hradecka (CZE)

Storm Sanders v Alexandra Dulgheru (ROM)

Priscilla Hon  v Annika Beck (GER)

Qualifier v 25-Samantha Stosur

21-Ekaterina Makarova (RUS) v Maddison Inglis

Kimberly Birrell v 9-Karolina Pliskova (CZE)

Qualifier v Jarmila Wolfe

Tammi Patterson v 20-Ana Ivanovic (SRB)

Possible quarter-finals

Men:

1- Novak Djokovic (SRB) v 7- Kei Nishikori (JPN)

3- Roger Federer (SUI) v 6- Tomas Berdych (CZE)

5- Rafael Nadal (ESP) v 4- Stan Wawrinka (SUI)

8- David Ferrer (ESP) v 2- Andy Murray (GBR)

Women:

1- Serena William (USA) v 5- Maria Sharapova (RUS)

4- Agnieszka Radwanska (POL) v 6- Petra Kvitova (CZE)

7- Angelique Kerber (GER) v 3- Garbine Muguruza (ESP)

8- Venus Williams (USA) v 2- Simona Halep (ROU)