World number three Novak Djokovic opened the defence of his Toronto Masters title in impressive style with a 6-4 6-4 win over Canadian Frank Dancevic [Images] on Tuesday.

The Australian Open champion was joined in the third round by sixth seeded American Andy Roddick [Images], who launched his hardcourt campaign earlier in the day with a battling 6-1, 6-7, 6-3 win over Frenchman Nicolas Mahut.

World number one Roger Federer [Images] and Wimbledon champion Rafael Nadal [Images] open their accounts on Wednesday after receiving first round byes in the $2.6 million event.

Playing in his first event since a second-round loss to Marat Safin [Images] at Wimbledon, Djokovic took a little time to shake off the rust but soon got into his stride and broke Dancevic to take the opening set.

The 21-year-old Serb recorded an early break in the second to push 4-2 ahead but then wobbled as Dancevic, urged on by a raucous home crowd, staged a late rally by breaking back and holding serve.

But Djokovic responded with another decisive break to seal the match in 77 minutes.

"I was aware he had nothing to lose, the big Canadian hope playing in front of his crowd with big support," said Djokovic.

"Always the first match is the trickiest one, trying to keep the balance.

"There were some things that I was not really happy about but it is still only the first match."

Roddick, also back in action for the first time since a second round loss at Wimbledon, swept through the first set as dark clouds gathered above centre court but was unable to sustain the momentum in the second.

The 26-year-old Mahut fought back to level the match after taking the second set in a tie-break.

Roddick rediscovered his touch in the third set, the 2003 Toronto champion breaking Mahut at the first opportunity on the way to a 3-0 lead before closing out the match with his 18th ace.

"I thought I moved well and most importantly I felt well physically," said Roddick, who has been hampered by a sore right shoulder.

"Hopefully my problems are behind me and I can play good tennis again."

Frenchman Gilles Simon, who won at Indianapolis on Sunday, crushed 18-year-old American qualifier Donald Young 6-1 6-3 to set up a second-round meeting with Federer, a two-times champion on the Canadian hardcourts.

Nadal will meet Jesse Levine after the American qualifier beat Canadian wildcard Peter Polansky 6-2 6-4.

Czech 16th seed Tomas Berdych cruised into the second round with a 6-3 6-1 win over Finland's Jarkko Nieminen.

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