The Australian Open lost its second seeded player in two days with yesterday's withdrawal of world number three Venus Williams.
Williams, the elder sister of US Open champion Serena, pulled out of next week's first grand slam of the year, citing tendonitis in her left wrist.
Her exit follows Monday's news that four-time Australian Open champion Monica Seles had failed to recover in time from a foot injury.
Pete Sampras, meanwhile, beat Richard Krajicek of the Netherlands 6-4 3-6 7-6 in his opening match of the Colonial Classic tennis tournament in Melbourne yesterday.
Warming up for the Australian Open, the reigning Wimbledon champion struggled at times against the big Dutchman but wrapped up the match by taking the final-set tiebreak 7-5 when Krajicek hit a forehand long after one hour and 54 minutes.
The win earned Sampras a meeting with another big-hitter, Australia's Mark Philipppoussis, who beat Australian Open champion Yevgeny Kafelnikov 7-6 6-7 6-1 earlier yesterday at the event.
Andre Agassi, also using the event to fine-tune his Australian Open preparation, beat South Africa's Wayne Ferreira 6-2 6-4.
The eight-man Colonial Classic is being played on the same type of hardcourt used at the Open, which starts on Monday.
At the Sydney International yesterday the world number two Lindsay Davenport and Russian Anna Kournikova reached the quarter-finals as they prepare for the Open. Second seed and defending champion Davenport needed just 45 minutes to blow Russia's Elena Likhovtseva off centre court at Homebush Bay with a clinical 6-1 6-2 win.
Eighth seed Kournikova, yet to win a tournament in 66 previous starts, stumbled through a sloppy match against former teen prodigy Jennifer Capriati. The teenager slumped to 1-4 in the first set before clawing past an error-prone Capriati to win 6-4 7-5.
In the men's draw at the new Sydney Olympic tennis centre, Australian teenager Lleyton Hewitt extended his unbeaten run this year to seven matches with a 6-3 6-2 second round defeat of Francisco Clavet.