When Amelie Mauresmo sat down for her pre-tournament news conference at the French Open, the chair broke. She took a tumble, then rose with a laugh, able to shake off her latest collapse at Roland Garros. When the tournament begins Sunday, the Frenchwoman will be more than the hometown favorite. She’s ranked No.

If Roger Federer and Rafael Nadal are going to build a rivalry for the ages, it wouldn’t hurt the TV ratings or buzz factor if there were a bit of animosity — or at least a difference of opinion. Well, it looks like they’ve got the latter. Both usually say all the right things about the other’s talent and place in the game, but a touch of tension arises when it comes to Federer’s contention that…

Prospects for U.S. women at the French Open already seemed bleak, what with Serena Williams and Lindsay Davenport sidelined, and Venus Williams a bit rusty. After Friday’s draw, things look about as tough as could be. Of the 12 Americans in the women’s field, Venus Williams is the only one who’s seeded, and most of the 11 others drew top opponents right from the start.

Two-time champion Serena Williams withdrew from Wimbledon on Friday because of a chronic knee injury. She had also withdrawn from the French Open, which starts Sunday. Wimbledon starts June 26. Williams won Wimbledon in 2002 and 2003, beating her older sister Venus in both finals. She reached the third round last year, while Venus won the title for the third time.

Top-ranked Amelie Mauresmo and No. 3 Maria Sharapova withdrew Sunday from the Italian Open, an important clay-court tuneup for the French Open. Mauresmo, the two-time defending champion in Rome, said she had a cold and fever. Sharapova has a bruised bone in her right ankle. Mauresmo lost to Justine Henin-Hardenne in the German Open semifinals Saturday.

Lleyton Hewitt has withdrawn from next week’s Hamburg Masters Series tennis tournament because of a calf muscle injury, his management team said in a statement Friday. The injury means Hewitt will play the second Grand Slam of the year with only one clay-court warmup tournament — at Poertschach, Austria, beginning May 22, one week before the French Open.

Top-ranked Roger Federer and No. 3 David Nalbandian reached the quarterfinals of the Rome Masters on Thursday. Federer dispatched 14th-seeded Radek Stepanek of the Czech Republic 6-1, 6-4 in 56 minutes, while Nalbandian beat Alberto Martin of Spain 7-5, 6-4 for his eighth straight victory. The only trouble for Federer, who needed a second-set tiebreaker Wednesday to eliminate Italian wild card…

Martina Hingis beat fifth-seeded Elena Dementieva 6-3, 6-2 Thursday to reach the quarterfinals of the German Open. Defending champion Justine-Henin Hardenne joined Hingis in the next round with a 6-1, 6-0 rout of 15th-seeded Maria Kirilenko. Li Na of China won 6-1, 6-0 against Colombia’s Catalina Castano.

U.S. Davis Cup player Taylor Dent had back surgery Wednesday and hopes to return to the tour before Wimbledon. Dent was ranked as high as 21st last year but he’s only 1-4 in 2006 and has slipped to 65th on the ATP Tour. He hurt his back in Rotterdam in February. “This is a minor procedure and I hope to be back for the grass- court season,” Dent said in a statement distributed by the ATP.

Third-seeded Shahar Peer of Israel advanced to the quarterfinals of the Prague Open, beating Zuzana Ondraskova of the Czech Republic 7-6 (6), 0-6, 6-3 Wednesday. Also, sixth-seeded Maria Elena Camerin of Italy defeated Meghann Shaughnessy of the United States 7-5, 6-4, and eighth-seeded Alona Bondarenko of Ukraine upset Melinda Czink of Hungary 2-6, 6-0, 6-2.

Three-time champion Gustavo Kuerten will skip the French Open because of an injury, as will Igor Andreev — the last player to beat defending champion Rafael Nadal on clay. The 26th-ranked Andreev withdrew from the year’s second Grand Slam tournament with a knee injury and was replaced in the field Wednesday by Kenneth Carlsen of Denmark.

Top-seeded David Nalbandian beat Nikolay Davydenko 6-3, 6-4 Sunday to become the third two-time winner of the Estoril Open. Nalbandian — who won in 2002 — joins Carlos Costa of Spain (1992, ’94) and Thomas Muster of Austria (1995-96) as two-time winners. “To return four years later after the first triumph and to win again is very positive,” Nalbandian said.

Top-seeded Kim Clijsters defeated Svetlana Kuznetsova of Russia 7-5, 6-2 Sunday to win the clay court J&S Cup. The victory avenges a semifinal loss to Kuznetsova in last year’s J&S Cup. “She’s a very, very good clay-court player,” Clijsters said. “I was very aggressive and tried not to give her the opportunity to play her own game.” Serving at 5-5 in the first set, Kuznetsova pushed a forehand wide…