World number one Roger Federer [Images] recovered from an early fright to advance into the second round at the Estoril Open on Tuesday.

The Swiss hit 17 aces and wracked up 53 unforced errors in his 4-6, 6-3, 6-2 victory over Olivier Rochus of Belgium.

Despite suffering four first round exits this year, the 27-year-old Rochus started confident and broke once for a 4-3 lead when Federer served a double fault. Rochus saved six break points in the first set.

Federer, without an ATP title since clinching his fourth Tennis Masters Cup title in Shanghai in November, failed to convert two break point opportunities in the fourth game of the second set.

But the pressure began to tell on the Rochus serve and Federer broke in the sixth game to take a 4-2 lead.

With greater composure on the sun-baked clay at the Estadio Nacional, Federer broke twice in the third set to wrap up his 12th victory of the season.

The Swiss player will meet Victor Hanescu of Romania in the second round.

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