Melbourne - Rafael Nadal will step up his bid for a record-equalling 20th Grand Slam title when he faces Argentina's Federico Delbonis at the Australian Open on Thursday.
The Spaniard can only count one Melbourne title among his 19 Majors but he will be confident of reaching the third round at least after winning all three previous meetings with Delbonis.
Swiss great Roger Federer, winner of 20 Grand Slam tournaments, and eight-time Australian Open champion Novak Djokovic are already through after straightforward wins.
Nadal has dropped only 10 games to 76th-ranked Delbonis in their previous meetings but he's not immune to Grand Slam shocks, losing four times to players ranked 100 or lower.
Victory in Melbourne would make Nadal the first man in the Open era - and only the third in history - to win all four Major titles twice, after Roy Emerson and Rod Laver.
Later on Thursday, Nick Kyrgios faces Frenchman Gilles Simon as he looks to become the tournament's first home-grown men's champion since Mark Edmondson in 1976.
Kyrgios is known for his combustible nature but after spearheading fundraising efforts for Australia's bushfire crisis he has cut a relatively calm figure in Melbourne - so far.
"I'm just playing for a lot more than myself. I've said it before... there's not necessarily added pressure. I feel like I'm playing for a lot of people," he said.
The 2014 champion Stan Wawrinka takes on Italy's Andreas Seppi and world number five Dominic Thiem is up against Australia's Alex Bolt, ranked 135 places lower.
In the women's draw, Wimbledon champion Simona Halep takes on Britain's Harriet Dart, and 2016 Melbourne winner Angelique Kerber faces Australia's Priscilla Hon.
Results on day three of the Australian Open Grand Slam at Melbourne Park on Wednesday:
Tennys Sandgren (USA) bt Matteo Berrettini (ITA x8) 7-6 (9/7), 6-4, 4-6, 2-6, 7-5
Sam Querrey (USA) bt Ricardas Berankis (LTU) 7-6 (7/2), 4-6, 6-4, 6-4
Guido Pella (ARG x22) bt Gregoire Barrere (FRA) 6-1, 6-4, 3-6, 6-3
Marton Fucsovics (HUN) bt Jannik Sinner (ITA) 6-4, 6-4, 6-3
Tommy Paul (USA) bt Grigor Dimitrov (BUL x18) 6-4, 7-6 (8/6), 3-6, 6-7 (3/7), 7-6 (10/3)
John Millman (AUS) bt Hubert Hurkacz (POL x31) 6-4, 7-5, 6-3
Stefanos Tsitsipas (GRE x6) bt Philipp Kohlschreiber (GER) walkover
Milos Raonic (CAN x32) bt Cristian Garin (CHI) 6-3, 6-4, 6-2
Marin Cilic (CRO) bt Benoit Paire (FRA x21) 6-2, 6-7 (6/8), 3-6, 6-1, 7-6 (10/3)
Diego Schwartzman (ARG x14) bt Alejandro Davidovich (ESP) 6-1, 6-4, 6-2
Dusan Lajovic (SRB x24) bt Marc Polmans (AUS) 6-2, 6-4, 6-3
Yoshihito Nishioka (JPN) bt Daniel Evans (GBR x30) 6-4, 6-3, 6-4
Novak Djokovic (SRB x2) bt Tatsuma Ito (JPN) 6-1, 6-4, 6-2
Roger Federer (SUI x3) bt Filip Krajinovic (CRO) 6-1, 6-4, 6-1
Fabio Fognini (ITA x12) bt Jordan Thompson (AUS) 7-6 (7/4), 6-1, 3-6, 4-6, 7-6 (10/4)
Roberto Bautista Agut (ESP x9) bt Michael Mmoh (USA) 5-7, 6-2, 6-4, 6-1
Sara Sorribes (ESP) bt Veronika Kudermetova (RUS) 2-6, 6-1, 6-1
Anett Kontaveit (EST x28) bt Astra Sharma (AUS) 6-0, 6-2
Iga Swiatek (POL) bt Timea Babos (HUN) 6-3, 6-2
Carla Suarez (ESP) bt Aryna Sabalenka (BLR x11) 7-6 (8/6), 7-6 (8/6)
Elise Mertens (BEL x16) bt Danka Kovinic (MNE) 6-2, 6-0
Heather Watson (GBR) bt Kristyna Pliskova (CZE) 4-6, 6-3, 6-1
Anastasia Pavlyuchenkova (RUS x30) bt Nina Stojanovic (SRB) 6-1, 7-5
Taylor Townsend (USA) bt Jessica Pegula (USA) 6-4, 7-6 (7/5)
Ashleigh Barty (AUS x1) bt Polona Hercog (SLO) 6-1, 6-4
Elena Rybakina (KAZ x29) bt Greet Minnen (BEL) 6-3, 6-4
Alison Riske (USA x18) bt Lin Zhu (CHN) 6-3, 6-1
Julia Goerges (GER) bt Petra Martic (CRO x13) 4-6, 6-3, 7-5
Maria Sakkari (GRE x22) bt Nao Hibino (JPN) 7-6 (7/4), 6-4
Ekaterina Alexandrova (RUS x25) bt Barbora Krejcikova (CZE) 6-1, 6-3
Petra Kvitova (CZE x7) bt Paula Badosa (ESP) 7-5, 7-5
Naomi Osaka (JPN x3) bt Saisai Zheng (CHN) 6-2, 6-4
Cori Gauff (USA) bt Sorana Cirstea (ROU) 4-6, 6-3, 7-5
Shuai Zhang (CHN) bt Caty McNally (USA) 6-2, 6-4
Sofia Kenin (USA x14) bt Ann Li (USA) 6-1, 6-3
Ons Jabeur (TUN) bt Caroline Garcia (FRA) 1-6, 6-2, 6-3
Caroline Wozniacki (DEN) bt Dayana Yastremska (UKR x23) 7-5, 7-5
Qiang Wang (CHN x27) bt Fiona Ferro (FRA) 6-1, 6-2
Serena Williams (USA x8) bt Tamara Zidansek (SLO) 6-2, 6-3
Madison Keys (USA x10) bt Arantxa Rus (NED) 7-6 (7/3), 6-2