MELBOURNE, Australia — Venus Williams had played 251 Grand Slam matches and never once been forced to retire because of injury.
    It took all of four minutes for that streak to end.
    The seven-time major winner spent more than 48 hours agonizing over whether she'd be ready for the third round of the Australian Open. She decided to go ahead, hoping enough adrenalin would kick in to allow her to play through the pain.
    Williams was ailing after her second-round victory, her ability to move severely restricted. Waiting for her in the third round was 30th-seeded Andrea Petkovic. Williams took the court on a cool Friday night at Rod Laver Arena "just hoping for some magic."
    The match was over almost before it began. Williams won just one of the seven points she played before she bent over in pain, clutching her right side. She knew she had to stop.
    "A lot of times when you play ... you get this adrenalin that blocks pain," she said. "But I just didn't get enough of that today. Obviously, I just couldn't play. I couldn't move. It was too painful."
    The lunge to her right side on the last point aggravated a muscle in her hip that she hurt Wednesday night against Sandra Zahlavova. Her thigh was heavily bandaged when she walked on the court Friday.
    "The last 48 hours I did as much pain management and recovery that I could. I just hit some balls ... just kind of standing still," she said. "Just kind of warming up standing still and trying to give my best for the match.
    "I've never had to retire from a Grand Slam, especially after working so hard to pull out the match the other day. ... It's super disappointing because this is just not how I envisioned my Australian Open being."
    Things are looking far better for defending champion Roger Federer. The second-seeded Swiss beat Xavier Malisse 6-3, 6-3, 6-1, a vast improvement on his five-set second-round win over Gilles Simon.
    Top-seeded Rafael Nadal plays 18-year-old Australian wild card Bernard Tomic on Saturday night. The Spaniard is trying to become the first man since Rod Laver in 1969 to hold all four major titles at once. Nadal made a quarterfinal exit in Australia last year, then won the French Open, Wimbledon and the U.S. Open.
    No. 8 Andy Roddick overcame a slow start before powering to victory with 32 aces, stopping Robin Haase 2-6, 7-6 (2), 6-2, 6-2.
    No. 6 Tomas Berdych, No. 9 Fernando Verdasco and No. 19 Stanislas Wawrinka advanced. Wawrinka defeated No. 12 Gael Monfils 7-6 (4), 6-2, 6-3 and will meet Roddick in the next round.
    No. 3 Novak Djokovic, the 2008 Australian Open champion, was leading Viktor Troicki 6-2 when his Serbian Davis Cup teammate retired because of a stomach muscle strain.
    That was hours before Venus Williams stepped on the court. She was the only Williams sister in the draw, and had a lot to live up to. Younger sister Serena, the defending champion, withdrew because of a foot
injury.
    Their mother and coach, Oracene Price, said Venus should not have even traveled to Australia as well because of recent injuries. She spoke during the post-match news conference from a seat in the auditorium after Venus directed a question to her.
    Venus hasn't won a major since Wimbledon in 2008 and been in a Grand Slam final since Wimbledon in 2009. She's never won the Australian title, her best finish a runner-up to Serena in 2003.
    "Well, I'm still pretty good, even when I'm injured," she said, pointing to her run to the U.S. Open semifinals last September as evidence. "I mean, at the Open I came pretty close to winning that tournament just on a hope and a prayer and little to no preparation.
    "Here, you know I was grinding. So I'm just going to focus obviously on getting healthy and coming back. Because I love tennis and I've got a lot of great tennis in me. I love my job, so no end in sight."
    Justine Henin has retired once already, and came back to reach the Australian Open final last year in her return to Grand Slam tennis. Until she came back to Australia, she hadn't played a competitive match since Wimbledon because of an ailing right elbow.
    Like Venus Williams, Henin has won seven majors and been ranked No. 1. She had never lost in the Australia Open to anyone who hadn't been No. 1 at one time. She also had never lost in a major to Svetlana Kuznetsova.
    That changed Friday when Kuznetsova, a former French and U.S. Open champion once ranked No. 2, won 6-4, 7-6 (8). She completed the victory on her fourth match point after wasting two chances to serve for the match before the tiebreaker. This was Henin's worst showing at Grand Slam tournament since Wimbledon in 2005.
    Henin was only weeks into a comeback from a career break from the tour when she lost the final last year to Serena Williams, the third time in four appearances that she'd reached the championship match at Melbourne. Her comeback season was derailed when she injured her right elbow at Wimbledon and didn't play again in 2010.
    "There's no excuse, even if I know I'm not at 100 percent," Henin said. "She was better than me."
    With the Williams sisters and Henin out, U.S. Open champion Kim Clijsters is looking more and more like a possible winner. Clijsters, seeded third, plays in the third round Saturday against Alize Cornet of France. No. 2 Vera Zvonareva opens play at Rod Laver Arena against Lucie Safarova.
    No. 1 Caroline Woznicki is already into the fourth round following her 6-4, 6-3 win over Dominika Cibulkova on Friday. After that, she went on a charm offensive by running her own Q&A to entertain critics who thought she was boring at news conferences and didn't deserve the top ranking without a major title.
    French Open champion Francesca Schiavone advanced and will next play Kuznetsova. Li Na of China, who reached the Australian semifinals last year, set up a fourth-round match against No. 8 Victoria Azarenka.
    Maria Sharapova, the 2008 Australian Open champion, struggled to a 4-6, 6-4, 6-4 win over Julia Goerges of Germany. Her game picked up only after she asked officials to fix an air bubble on the Hisense Arena court.
    Her next match is against Petkovic, who has reached the fourth round at consecutive majors and barely played a point in the third round at either of them. Peng Shuai withdrew before their scheduled third-round match at the U.S. Open, and now Williams.
    "I'm not jinxing the other girls," she said. "I really feel terrible that everybody has to retire against me in the third round."
    She knew Williams was hurting but supported her decision to start the match.
    "I think she wanted to give it a try," Pekovic said. "I just hope she gets better because she's such a great champion."