A fit and fresh looking Djokovic, who was beaten by Andy Murray to the All England Club crown, showed little signs of rust from a lack of recent match practice as he took just 56 minutes to advance on a warm Montreal evening.
The Serbian, renowned for his sense of humour and reputation as an entertainer, then celebrated his victory with some impromptu dancing in the centre of the main arena, much to the delight of the fans who had stayed late to watch him.
"It's the first game (for me) since Wimbledon, I had four weeks off ... but it was a great performance," a smiling Djokovic said in a courtside interview once he had ended his crowd-pleasing antics.
The return of the two-time defending champion after a month off had followed Nadal's first competitive match since his shock first round exit at Wimbledon.
It proved to be a successful, yet tense, one for Nadal as he and his doubles partner Pablo Andujar saved two match points before they beat Spanish compatriots David Ferrer and Feliciano Lopez 6-7(2) 6-1 12-10.
The second day's play, however, belonged to the understated locals, including three wildcard entries who stunned their more highly fancied opponents as they basked in the home support.
World number 71 Vasek Pospisil produced the biggest upset when he surged to an unlikely first round win over in-form American John Isner.
Pospisil came from a set and a break down to claim a 5-7 7-6(5) 7-6(4) victory in bright and sunny conditions, thrilling a parochial home crowd who cheered his every winner.
Isner, who won the Atlanta title two weeks ago before being beaten by Juan Martin Del Potro in the Washington final last week, was left wondering how he had failed to get the job down.
"I should've won the match," Isner said. "I should've won the second set and I also should've won the third set but I didn't. This was a match I let slip away."
Frank Dancevic, another local wildcard, also rallied to beat Taiwan's Lu Yen-Hsun in three sets while Felip Peliwo became the fourth Canadian to reach the last 32 when Finland's Jarko Nieminen retired with a pulled hamstring trailing 3-1 in the deciding set.
Canada's top ranked player Milos Raonic then completed a memorable day for the hosts with a 6-3 4-6 7-5 triumph over Jeremy Chardy of France to become the fifth local into the second round.
"I'm really proud and happy for the (Canadian) guys who have been winning yesterday and today. It's really great to see," the world number 13 Raonic said.
Earlier world number 18 Jerzy Janowicz battled some internal demons before winning an error-strewn opening match on centre court against Frenchman Julien Benneteau.
Italian Fabio Fognini continued his impressive form with a three-set defeat of Marcos Baghdatis while 12th seed Gilles Simon and 14th seed Nicolas Almagro lost to former world number three Nikolay Davydenko and Czech Radek Stepanek respectively.
Montreal Masters results
7-Richard Gasquet (France) beat Martin Klizan (Slovakia) 6-3 6-2
1-Novak Djokovic (Serbia) beat Florian Mayer (Germany) 6-2 6-1
9-Kei Nishikori (Japan) beat Andreas Seppi (Italy) 4-6 7-5 6-1
10-Tommy Haas (Germany) beat David Goffin (Belgium) 7-6(4) 6-3
11-Milos Raonic (Canada) beat Jeremy Chardy (France) 6-3 4-6 7-5
Nikolay Davydenko (Russia) beat 14-Gilles Simon (France) 2-6 6-1 6-1
Alexandr Dolgopolov (Ukraine) beat Kevin Anderson (South Africa) 7-6(0) 6-4
Marcel Granollers (Spain) beat Grigor Dimitrov (Bulgaria) 6-4 6-4
Vasek Pospisil (Canada) beat John Isner (U.S.) 5-7 7-6(5) 7-6(4)
Frank Dancevic (Canada) beat Lu Yen-Hsun (Taiwan) 5-7 7-6(6) 6-1
Mikhail Youzhny (Russia) beat Jurgen Melzer (Austria) 6-4 7-6(3)
13-Fabio Fognini (Italy) beat Marcos Baghdatis (Cyprus) 1-6 6-1 6-1
15-Jerzy Janowicz (Poland) beat Julien Benneteau (France) 3-6 6-3 7-5
Filip Peliwo (Canada) beat Jarkko Nieminen (Finland) 3-6 7-5 3-1 (Nieminen retired)
Radek Stepanek (Czech Republic) beat 12-Nicolas Almagro (Spain) 6-3 6-7(4) 6-3
Alex Bogomolov Jr (Russia) beat Michael Llodra (France) 6-2 4-6 6-3