Venus Williams lasted just seven points in her third-round match yesterday at the Australian Open, forced to withdraw due to injury from a Grand Slam singles match for the first time in her career.

After losing the first game to Andrea Petkovic of Germany and trailing in the second, Williams stretched to her right to return a serve, hit the ball and then cried out in pain, clutching toward her stomach on her right side. It was soon clear that she couldn’t continue.

“Obviously I just couldn’t play,” Williams said. “I couldn’t move, it was too painful.”

Her right thigh was already heavily bandaged from an injury she sustained in the first set of her second-round match on Wednesday, when she beat Sandra Zahlavova in three sets. Afterward, Williams said the injury was in her “psoas” muscle, which flexes the hip and spinal column.

Williams, 30, waved to the Rod Laver Arena crowd and appeared to be on the verge of tears as she walked off the court. Her younger sister, defending champion Serena, didn’t even make it to Melbourne Park because of a foot injury.

Petkovic was surprised by the sudden end to the match.

“I feel very weird about how the things went,” said Petkovic. “It’s a pity, and I feel very sorry. I just hope she gets better — she’s such a great champion.”

Justine Henin left the tournament a lot sooner than she expected, too, but No. 1-seeded Caroline Wozniacki is still around, providing entertainment on and off the court.

Henin, the 2010 finalist, was beaten by two-time Grand Slam winner Svetlana Kuznetsova 6-4, 7-6 (8) in a mild third-round upset, while Roger Federer, Novak Djokovic, Andy Roddick and Maria Sharapova all advanced. Wozniacki provided as much fanfare in her post-match media conference as she did during her 6-4, 6-3 win over Dominika Cibulkova.

Henin and Kuznetsova didn’t have much fun following Wozniacki on the court. Kuznetsova twice had chances to serve out the match but Henin broke her both times.

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.

Sharapova, who won the 2008 Australian women’s title, struggled to a 4-6, 6-4, 6-4 win over Julia Goerges of Germany. French Open champion Francesca Schiavone of Italy also won, beating Monica Niculescu of Romania 6-0, 7-6 (2).

No. 9 Li Na of China, who reached the semifinals last year before losing in two tiebreaker sets to eventual champion Serena Williams, advanced 6-2, 6-1 over Barbora Zahlavova Strycova.

Schiavone and Kuznetsova, who will play each other in the fourth round, had what Kuznetsova called a misunderstanding after a Fed Cup match won by Italy over Russia.

Federer was back to his vintage best, beating Xavier Malisse 6-3, 6-3, 6-1. While the defending champion also won in straight sets in his opening-round match against Lukas Lacko, he was extended to five tough sets against Gilles Simon in the second round, a near five-hour match that Federer said he was he relieved to survive.

Yesterday at Rod Laver Arena, there was no such drama for the second-seeded Swiss star who is chasing his fifth Australian title. It took him 1 hour, 45 minutes to beat Malisse and earn an Open Era-record 57th match win at the Australian Open, breaking Stefan Edberg’s record.

Federer will play Tommy Robredo, who beat Ukraine’s Sergiy Stakhovsky 5-7, 6-2, 6-4, 6-2.

Roddick overcame a slow start before powering to victory with 32 aces to beat Robin Haase 2-6, 7-6 (2), 6-2, 6-2. The eighth-seeded Roddick is seeking to win his second Grand Slam nearly seven years after his first — the 2003 US Open.

Djokovic only had to play one set in the third round to advance. The 2008 Australian Open champion was leading Viktor Troicki 6-2 when his Serbian Davis Cup teammate retired due to a stomach muscle strain. Djokovic will play No. 14 Nicolas Almagro, who beat No. 17 Ivan Ljubicic 6-4, 7-6 (8), 6-3.

Ninth-seeded Fernando Verdasco advanced with a 6-2, 6-4, 6-3 win over Kei Nishikori of Japan and will play Tomas Berdych in the fourth round. The sixth-seeded Berdych beat Richard Gasquet of France 6-2, 7-6 (3), 6-2.

Stanislas Wawrinka of Switzerland beat 12th-seeded Gael Monfils 7-6 (4), 6-2, 6-3, breaking the French player in the last game. Warwinka will play Roddick in the fourth round.