Toronto - Novak Djokovic struggled to close out his opening win at the Rogers Cup on Wednesday with the Serb second seed requiring multiple match points to down Frenchman Julien Benneteau 7-5, 7-5.
The 2007 champion in Canada smashed a racket in frustration before finally improving to 4-1 in his career series against Benneteau.
Djokovic took to the court for the first time since leading his country into the Davis Cup semi-finals last month.
World number two Djokovic needed almost two and a quarter hours to get the job done in sweltering conditions on the Toronto hardcourts where he was out-aced nine to six by his 33rd-ranked opponent, whom he beat in the Wimbledon first round.
Djokovic will next face Romanian Victor Hanescu, who denied Peter Polansky the chance to to become the first Canadian into the third round at home since 2007, earning a 6-4, 7-6 (7/4) win.
"I'm very happy the way I played, and I think Polansky played very well today," said Djokovic, who has defeated the Canadian four times.
"It was very close, he had some chances. Maybe I was more focused, maybe more concentrated, anyway, finally I won."
Russia's world number six Nikolay Davydenko beat Italian Fabio Fognini 7-5, 6-1 but Ukranian Alexandr Dolgopolov upset 12th seed Russian Mikhail Youzhny 1-6, 7-6 (7/4), 7-5.
Last week's Washington winner David Nalbandian continued his comeback success from hip surgery and other injuries, putting out Spain's Tommy Robredo 6-3, 6-0.
Including two Davis Cup wins in April before an extended injury absence, the Argentine has now won his last ten matches.