OEIRAS, Portugal — Roger Federer captured his first singles win on clay this season, beating Bjorn Phau of Germany 6-3, 6-4 at the Estoril Open on Wednesday.

The world No. 1 conceded just 17 points on his service game as he rebounded from a first-round loss in Rome last week.

"It was a very important match for me today," Federer said.

Federer, who had a bye into the second round at Estoril, will meet Arnaud Clement of France in the quarterfinals. Federer won the Estoril crown in 2008 but skipped last year's event.

The Rome Masters, where he lost against 40th-ranked Ernests Gulbis, was Federer's first singles match in nearly a month. He took off several weeks after losing in the fourth round at Key Biscayne at the end of March.

Fourth-seeded Albert Montanes, the defending champion, ousted fellow Spaniard Daniel Gimeno-Traver 6-1, 6-2 and next plays eighth-seeded Pablo Cuevas. The Uruguayan overcame Marcel Granollers of Spain 7-6 (8), 7-6 (2).

Second-seeded Sorana Cirstea of Romania advanced in the women's event with a 7-5, 7-5 victory over Michelle Larcher de Brito of Portugal.

Fourth-seeded Anabel Medina Garrigues of Spain and seventh-seeded Peng Shuai of China also advanced.