World number one Roger Federer [Images] and defending champion Rafael Nadal [Images] returned from vacation to post routine first-round wins at the Toronto Masters on Tuesday.

Back in action for the first time since the Wimbledon final won by Federer, the Swiss celebrated his 25th birthday by easing past Frenchman Paul-Henri Mathieu 6-3, 6-4 as Nadal shook of some rust with 6-3, 6-2 victory over Chile's Nicolas Massu.

The world's two outstanding players, Federer and Nadal have met in five finals this year and appear headed for another mouth-watering showdown on Sunday.

The muscular Spaniard and the silky smooth Swiss have taken ownership of the men's game, winning six of the last seven grand slams and 12 of 14 Masters Series events, including the last two Toronto Masters.

Federer, who spent his month off savouring his fourth consecutive Wimbledon title at his training and holiday base in Dubai, was typically efficient, improving his season's hardcourt record to 29-1 with his only loss to Nadal in the Dubai final.

Federer, the 2004 Toronto champion, will next meet in-form Frenchman Arnaud Clement, who won his second title of the season on Sunday in Washington and strolled into the second round by crushing Spain's Alberto Martin 6-1, 6-2.

"I was home last year so it's good to be back on the road again for my birthday," said Federer, who was presented with a cake while the centre court crowd sang Happy Birthday to the eight-times grand slam winner.

"I was very relaxed going into today's match, even though I knew the opponent can be very dangerous," he added. "To play so well is always a bit of a surprise in the first round.

"These Masters Series are really, really tough from the first round on. To come through was a good sign."

FEISTY CHILEAN

After a month layoff spent fishing and visiting Euro Disney, Nadal laboured against the feisty Chilean, particularly in a tough opening set that lasted 68 minutes.

But after nearly two hours under a broiling sun, the second seed declared himself satisfied.

"After one month it is difficult to get the rhythm," said Nadal. "It is very difficult the first round after a month off.

"The most important thing is to win, and I win, so I am very happy. I played a simple match, nothing special for sure."

The momentum from claiming his second title of the season in Poland on Sunday was not enough to carry a weary Nikolay Davydenko to victory as the Russian sixth seed suffered a first-round shock, falling 6-3, 7-5 to Belgian Xavier Malisse. He joined third seed David Nalbandian and No. 10 Marco Baghdatis on the casualty list.

Marat Safin's [Images] up and down season continued when the Russian was bundled out in the first round 7-5, 5-7, 6-2 by seventh seed Tommy Robredo of Spain.

German 16th seed Tommy Haas continued his domination of Max Mirnyi, disposing of the Belarussian 6-3 ,6-3 to register his eighth win in nine career meetings.

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