Among the seeded stars to join him in the second round were Daniil Medvedev and Dominic Thiem. Fourth seed Medvedev beat Frances Tiafoe 6-3, 4-6, 6-4, 6-2 and has now made the second round in each of his last three runs at the Australian Open, while fifth seed Thiem thrashed Adrian Mannarino 6-3, 7-5, 6-2.
Like that duo, Alexander Zverev is still waiting on his maiden major and will continue his search at the Australian Open having defeated Marco Cecchinato 6-4, 7-6 (4), 6-3 to advance.
Karolina Pliskova and Simona Halep led the charge of top women's seeds who also progressed to the second round, notching victories over respective opponents Kristina Mladenovic and Jennifer Brady on Day 2.
Elina Svitolina and Belinda Bencic—seeded fifth and sixth, respectively—knocked Katie Boulter and Anna Karolina Schmiedlova out of the running as they progressed with a pair of straight-sets victories.
American star Madison Keys reached the second round of the Australian Open for a seventh time following her 6-3, 6-1 triumph over Daria Kasatkina, who fell at the first hurdle for a third time in Melbourne.
Tuesday's Key Results
(1) Rafael Nadal bt. Hugo Dellien: 6-2, 6-3, 6-0
(4) Daniil Medvedev bt. Frances Tiafoe: 6-3, 4-6, 6-4, 6-2
(5) Dominic Thiem bt. Adrian Mannarino: 6-3, 7-5, 6-2
(7) Alexander Zverev bt. Marco Cecchinato: 6-4, 7-6 (4), 6-3
(12) Fabio Fognini bt. 3-6, 6-7 (3), 6-4, 6-3, 7-6 (5)
(15) Stanislas Wawrinka bt. Damir Dzumhur: 7-5, 6-7 (4), 6-4, 6-4
(23) Nick Kyrgios bt. Lorenzo Sonego: 6-2, 7-6 (3), 7-6 (1)
(24) Dusan Lajovic bt. Kyle Edmund: 7-6 (7), 6-3, 7-6 (4)
(27) Pablo Carreno-Busta bt. Jozef Kovalik: 6-4, 3-6, 6-1, 7-6 (2)
Alexei Popyrin bt. (28) Jo-Wilfried Tsonga: 6-7 (5), 6-2, 6-1, 0-0 (retired)
Ernests Gulbis bt. (20) Felix Auger-Aliassime: 7-5, 4-6, 7-6 (4), 6-4
(2) Karolina Pliskova bt. Kristina Mladenovic: 6-1, 7-5
(4) Simona Halep bt. Jennifer Brady: 7-6 (5), 6-1
(5) Elina Svitolina bt. Katie Boulter: 6-4, 7-5
(6) Belinda Bencic bt. Anna Karolina Schmiedlova: 6-3, 7-5
(9) Kiki Bertens bt. Irina-Camelia Begu: 6-1, 6-4
(10) Madison Keys bt. Daria Kasatkina: 6-3, 6-1
(17) Angelique Kerber bt. Elisabetta Cocciaretto: 6-2, 6-2
(19) Donna Vekic bt. Maria Sharapova: 6-3, 6-4
(26) Danielle Collins bt. Vitalia Diatechenko: 6-1, 3-6, 6-4
Ons Jabeur bt. (12) Johanna Konta: 6-4, 6-2
Zarina Diyas bt. (21) Amanda Anisimova: 6-3, 4-6, 6-3
Ajla Tomljanovic bt. (31) Anastasija Sevastova: 6-1, 6-1
Visit the Australian Open website to see the results in full.
Nadal looked increasingly confident en route to his opening-round win at the Rod Laver Arena and fittingly sealed his victory with a bagel to end Dellien's hopes of an upset, via Nine News Melbourne:
The Spaniard is seeking his 20th career Grand Slam in Melbourne but hasn't won the title here since 2009, his longest title drought in any of the four majors.
While one of the sport's most revered veterans sauntered to victory, the younger Medvedev, Thiem and Zverev also joined him in the second round with wins of their own.
Fourth seed Medvedev was challenged in an awkward meeting opposite American Tiafoe, while Thiem and Zverev looked more at ease clinching straight-sets wins.
Zverev's serve has been a particular concern of late, but both he and German compatriot Angelique Kerber showed composure clinching a pair of clean wins, per Live Tennis:
Jo-Wilfried Tsonga retired when he was 6-7 (5), 6-2, 6-1 down to Australia's Alexei Popyrin, while Italy's Fabio Fognini looked to be on the verge of his own first-round exit to Reilly Opelka.
Fognini rallied from two sets down to beat Opelka 3-6, 6-7 (3), 6-4, 6-4, 7-6 (5) and complete a rare Slam of his own, per Ben Rothenberg of the New York Times:
Ben Rothenberg @BenRothenberg
Fabio Fognini = King of Comebacks (also unnecessary deficits). He's completed the #SlingshotSlam, coming back from two sets down at: #AusOpen: 2020 Opelka French Open 2010 Monfils Wimbledon: 2010 Russell; 2014 Kuznetsov US Open: 2012 Roger-Vasselin; 2015 Nadal; 2016 Gabashvili
Stanislas Wawrinka's 7-5, 6-7 (4), 6-4, 6-4 win over Damir Dzumhur extended his Australian Open first-round record, which is superior to even Nadal's:
Pliskova made relatively light work of Mladenovic and advanced following her 6-1, 7-5 triumph, with the second seed facing Germany's Laura Siegemund in the next round.
Fourth seed Halep looked set for a first-round upset opposite Brady, and AFP's Reem Abulleil described the extent of her 7-6 (5), 6-1 comeback win after a testing first set:
She'll next face Harriet Dart, who recovered from a slow start to edge Misaki Doi 2-6, 6-4, 7-6 (6) to ensure at least one female Briton will line up in the next phase:
Compatriots Johanna Konta (No. 12 seed) and Boulter each fell out of the women's singles on Tuesday, while Heather Watson is set to face Kristyna Pliskova in her first-round matchup.