MELBOURNE, Australia -- Venus Williams overcame a painful knee injury to limp past fellow American Kristina Brandi 6-3, 6-4 and into the third round of the Australian Open on Wednesday.

	Venus Williams advanced to the third round, then welcomed Thursday off after injuring her ankle against Kristina Brandi.

Williams, seeded second, stretched her unbeaten streak to 22 matches. Her younger sister, No. 5 seed Serena, withdrew from the Grand Slam tournament before it started due to an ankle injury.

Venus Williams, who had a patch on her left knee, dropped serve when leading 5-2 in the second set, but clinched it with her second match point when Brandi put a backhand in the net.

"God's blessed me to be able to get through this round," said Williams, the U.S. Open and Wimbledon champion, who hopes that a rest day Thursday will help her recover.

"Serena wasn't able to play, so I'll give it my all to hang around," Venus said. She hurt the knee just 20 minutes before the match, but she's not sure how.

"Sometimes those old pains revisit you at the most inopportune times," she said. "My trainer did really well just to keep me out there."

Also reaching the third round -- but with ease -- was Martina Hingis, who hammered German qualifier Greta Arn 6-1, 6-2 and kept her return from injury on track.

Hingis, Australian Open champion from 1997-99, is playing her first big tournament since tearing ligaments in her right ankle in Filderstadt last October.

The Swiss said she had profited from her long break from tennis since surgery on her damaged ankle.

"I had a long break to recover...it did me well because I could kind of recover mentally and physically," she told a media conference.

"I'm very happy the way things have gone."

The No. 3 seed, who hasn't captured a Grand Slam title since winning in Melbourne in 1999, dominated all parts of the match against her inexperienced opponent.

Arn, 22, tried to unsettle Hingis by rushing the net wherever possible but the cool Swiss was content to stay on the baseline and dictate the terms of the match against the German, who held her serve for the first time in the fifth game of the second set.

Arn's error count of 31 to Hingis's seven was the most telling statistic from the match, which lasted just 56 minutes on Melbourne Park's Vodafone Arena.

Hingis said she was happy to have reached the third round with a minimum of fuss after two straight sets victories.

"Now it kind of starts off in the third, fourth round, then definitely the second week," she said.

The withdrawal Serena Williams has cleared the way for a possible semifinal showdown between Hingis and Venus Williams, who said she was taping her knee for future rounds in Melbourne.

She said had this not been a Grand Slam event it is unlikely she would have played.

"I've played Kristina before and know her game," Williams said. "I was hoping I would put a little extra mustard on the ball and get through it. But against one of the heavy-hitters, I don't think so."

Hingis's failure since 1999 to add to her list of five Grand Slam titles has coincided with the rise of players like the Williams sisters and Jennifer Capriati, who all rely heavily on power games.

Hingis said she had used her time since the surgery to work on her fitness but saw little point in trying to build her strength to the point where she might be able to slug it out with the Williams sisters and Capriati, who beat her in last year's Melbourne final.

Asked about her training regime since the injury, Hingis said: "Lots of tennis, lots of hours spent on the court every day, four hours every day then running in the mountains."

"I'm never going to a be a power junkie...I have to work on my methods," she said.

Former world No. 1 Monica Seles breezed into the third round with a 6-1, 6-1 victory against Cara Black.

Seles, Australian Open champion four times between 1991 and 1996, hardly put a foot wrong as she coasted to victory in 53 minutes.

The only hiccup the Yugoslav-born American made was in the second set when she failed to serve out the match at 5-0, but she quickly made amends by breaking Black's next service game to seal an easy victory.

"It's great to be back here and playing well again," said Seles, who won the last of her nine Grand Slam titles with an emotional victory at the 1996 Australian Open. "This is my favorite tournament."

Seles will play either Francesca Schiavone or Jelena Kostanic in the third round with a possible quarterfinal against tournament favorite Venus Williams looming.

No. 13 Magdalena Maleeva defeated Czech player Kveta Hrdlickova 6-4, 7-5, No. 15 Amanda Coetzer ousted Paraguay's Rossana Neffa-De Los Rios 6-3, 6-1, and No. 18 Lisa Raymond beat American compatriot Jill Craybas 6-3, 6-3.

Spain's Conchita Martinez, the 1994 Wimbledon champion and 1998 Australian and 2000 French runner-up, lost 6-4, 6-1 to Sweden's Asa Svensson, ranked 104th.

Information from The Associated Press and Reuters was used in this report.