Top seed and four-time champion opened his title defence with a 6-3, 6-3 win over Denis Istomin of Uzbekistan on Tuesday.
Novak advanced to the second round of the 2014 Australian Open with a 6-3, 7-6 (2), 6-1 win over Lukas Lacko of Slovakia on Monday.
Novak opened his title defence in convincing fashion, beating Lukas Rosol 6-0, 6-3 in just 53 minutes on Tuesday.
The 2011 US Open champion defeated Ricardas Berankis 6-1,
6-2, 6-2 in just 82 minutes to reach the 2nd round in New York.
Nole opened his campaign for a second Wimbledon title on Tuesday with a 6-3, 7-5, 6-4 victory over world no.34 German Florian Mayer.
Top-seeded Nole opened his 2013 French Open campaign with a 7-6 (6), 6-4, 7-5 win over David Goffin in two hours and 13 minutes.
Nole opened his Dubai Duty Free Tennis Championships campaign with a 6-1, 6-4 win over Viktor Troicki and set up second round match against Spaniard Roberto Bautista Agut.
Defending champion is through to the second round of the Australian Open with a comfortable 6-2, 6-4, 7-5 win over Frenchman Paul-Henri Mathieu in 1 hour and 42 minutes.
Novak opened his 2012 China Open campaign with a 6-1, 6-7(3), 6-2 win over German qualifier Michael Berrer.
World no.2 opened his US Open title defence campaign with a convincing 6-1, 6-0, 6-1 victory over no.69-ranked Italian Paolo Lorenzi in just 73 minutes.