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 Madinah Garrigues of Spain and seventh-seeded Peng Shuai of China also advanced.
 

His opening match delayed 24 hours by rain, top-seeded Marin Cilic of Croatia showed no distraction as he handled Michael Berrer of Germany 6-4, 6-2 at the BMW Open in Munich on Wednesday.

Cilic defeated Berrer in the final at Zagreb in February for his second title of the year.

Defending champion Tomas Berdych of the Czech Republic reached the quarterfinals by defeating Spanish qualifier Pere Riba 7-5, 6-1. Last year’s runner-up Mikhail Youzhny of Russia, also went through to the last eight by beating Andreas Beck of Germany 6-3, 6-3 in a match interrupted by rain.

Jan Hajek of the Czech Republic made the first quarterfinals by defeating eighth-seeded Benjamin Becker of Germany, 6-4, 6-0.

In first-round play, fourth-seeded Philipp Kohlschreiber ousted German compatriot Daniel Brands 6-4, 6-4, and sixth-seeded Nicolas Almagro of Spain beat Kristof Vliegen of Belgium 6-3, 6-1.
 

In Rome, top-ranked Serena Williams reached the Italian Open quarterfinals in her first tournament in three months after defeating Andrea Petkovic of Germany 6-2, 3-6, 6-0 on Wednesday.

Older sister Venus Williams ousted Shahar Peer of Israel 6-3, 6-4. Both sisters are back from knee injuries, and could meet in the semifinals.

Serena had been off the tour since she won the singles and doubles at the Australian Open, and she was entered in Rome thanks to a wild card.

Against the 49th-ranked Petkovic, Serena said she felt “rusty.” Her game was erratic at times and a mid-match slump cost her the second set. In the end she had almost as many winners as unforced errors, 25 to 21.

“I definitely felt extremely rusty today,” Serena said. “I’m glad I was able to win because at least I can be guaranteed another match. I think I definitely need it.”

Serena got off to a good start, winning the first set with a five-game streak. But she quickly fell 4-1 behind in the second, came back to 4-3 but conceded another, decisive break to Petkovic. In the third set, she picked up her game and played aggressively.

Serena next plays Maria Kirilenko of Russia, who defeated Dominika Cibulkova of Slovakia 4-6, 6-1, 6-1.

Serena said that after her three months off she needs to stay healthy and have match play. That’s why, she explained, she decided to skip social events at home and come to play the clay-court event in Rome instead.

Serena said she told herself to “forget Oprah and Anna Wintour” — who co-chaired the annual Metropolitan Museum of Art’s Costume Institute Gala Benefit on Monday in New York.

“I was supposed to be there. I had a fabulous dress,” Serena said. “It hurt me … I wanted to really be there but this is my career and I need the extra match.”

The fourth-seeded Venus, who had been sidelined with a knee problem since losing the Key Biscayne final, was solid against Peer. In the first set, she dropped only four points on serve and in the second she saved two break points at 3-4 before getting the decisive break in the next game.

Venus said she was especially happy with her serve and movement on clay.

She will have a tough quarterfinal against Jelena Jankovic, who was in impressive form as she rolled to a 6-2, 6-0 victory over Yanina Wickmayer of Belgium.

The Serb player ousted Venus in the 2008 quarterfinals on her way to her second Rome title.

In other action at the Foro Italico, Nadia Petrova of Russia won 6-0, 3-6, 6-2 against Alexandra Dulgheru of Romania, who knocked out defending champion Dinara Safina on Tuesday.