Nadal could be on a collision course with Federer again

The Spaniard, the defending champion, dropped just five games as he breezed past Chile's Nicolas Massu 6-3 6-2.

"When I saw the draw, I said it's not an easy match," said Nadal, who now faces Korean Lee Hyung-Taik.

Top seed Federer celebrated his 25th birthday by beating France's Paul-Henri Mathieu 6-3 6-4 to reach round two.

These Masters Series are really, really tough from the first round on Roger Federer

Federer, the world number one and Toronto champion in 2004, will now meet Sebastien Grosjean, another Frenchman.

"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 on centre court while the crowd sang "Happy Birthday".

"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."

Sixth seed Nikolay Davydenko failed to join Nadal and Federer in round two, losing 6-3 7-5 to Belgian Xavier Malisse.

Seventh seed Tommy Robredo beat Marat Safin 7-5 5-7 6-2 while German 16th seed Tommy Haas continued his domination over Max Mirnyi, beating the Belarussian 6-3 6-3 to notch his eighth win in nine career meetings.