The two teenagers traded 36 strokes, scrambling from side to side in a baseline rally so breathtaking that it left Martina Hingis panting and leaning against the back wall.
The point ended when Hingis swatted a forehand long. That gave upstart Williams two match points at 15-40, 3-5 in the third set of their thriller Tuesday at the Lipton Championships.
But the top-ranked Swiss Miss escaped unscathed and edged Williams 6-3, 1-6, 7-6 (7-4) in the quarterfinals.
That’s one Williams down and one to go for Hingis, the defending champion. In Thursday’s semifinals she’ll play Serena’s sister, Venus, who beat Silvia Farina 6-1, 6-2. Anna Kournikova beat Conchita Martinez in a fourth-round mismatch 6-3, 6-0.
In men’s fourth-round play, second-ranked Petr Korda squandered his chance to overtake No. 1 Pete Sampras in the rankings next week by losing to Tim Henman 6-4, 6-4. Sampras was eliminated Monday by Wayne Ferreira.
Steve Campbell, a 27-year-old journeyman from Detroit, became the first qualifier in Lipton history to reach the men’s quarterfinals by beating Ferreira 6-7 (3-7), 6-2, 7-5.
Third-ranked Marcelo Rios, who could become No. 1 if he wins the tournament, beat Goran Ivanisevic 6-2, 6-3. No. 5 Greg Rusedski and No. 6 Yevgeny Kafelnikov were eliminated.