By Steve Keating

TORONTO, Aug 10 (Reuters) - Roger Federer launched his North American hardcourt campaign with a workmanlike 7-6 6-3 win over Argentine Juan Ignacio Chela to move confidently into the third round of the Toronto Masters on Tuesday.

Twice a champion in Canada, it seemed business as usual for Federer when he strolled onto a packed center court to the cheers of an adoring crowd.

But while the surroundings were familiar, the situation was not as Federer has surrendered the number one world ranking he held for 285 weeks and entered a tournament as the third seed for the first time since November 2003.

Playing in his first tournament since a shock quarter-final exit at the All-England Club, Federer needed a few games to knock off some rust.

"It's always nice to come back after six weeks and get the win," Federer told reporters. "It's normal that you're a bit rusty after six weeks. You have to work your way into playing matches again."

Federer celebrated his 29th birthday on Sunday with cake and talk that his career was on the decline. But if there has been a drop off in Federer's game, there were no signs during the 81 minutes he spent on court against Chela.

The 16-time grand slam winner grabbed the early break to go up 4-2. But the Swiss maestro then began to misfire as he sent shots wide and long to let Chela back into the set before prevailing in the tiebreaker.

Federer again took the initiative in the second set with an early break and this time remained in control cursing to a comfortable win.

"I think I really did some good things out there and a bit of a pity I had a letdown at 5-2 up in the first set, because I think I really had things going my way then," said Federer.

"He played well to come back into it and after that I thought I still was able to dominate."

SUPERB FORM

Coming off a victory at the Washington Classic, Argentine David Nalbandian carried his superb form into Canada battling past 10th seeded Spaniard David Ferrer 7-5 3-6 6-3.

After missing most of last season recovering from hip surgery, Nalbandian was back on the sidelines in April with a hamstring injury that kept him out for two months.

The 28-year-old returned to represent Argentina in Davis Cup against Russia last month by winning both matches and has gone undefeated stringing together nine straight victories.

Robin Soderling, who could replace Briton Andy Murray as the world number four if the defending champion struggles in Toronto, advanced to the third round with a 4-6 6-4 6-4 win over young Latvian Ernests Gulbis.

Wimbledon finalist Tomas Berdych had a smoother passage with a 6-2 6-4 win over Ukraine's Sergiy Stakhovsky.