The quarter final thrashing of the player who started her big rise by winning this title when it was played down the road at Grand Champions last year was all the more surprising as Williams had beaten Pierce handily in their two previous meetings.
"I've never played a match where my opponent played pretty much impeccable the way she did today," said Serena who was full of praise for her opponent.
Having failed against Williams before, Pierce said she went into the match feeling very relaxed because she felt she had nothing to lose. � decided to go for it more," said the French Fed Cup player who was born in the States and raised in Canada. � just added at least ten miles an hour to my serve and tried to hit deeper."
Pierce hit too deep and too accurately for Williams who looked a little slow and slapdash by the end of a brief match on another day of scorching sunshine.
Pierce will now play Martina Hingis in the semi final following the Swiss player's 6-3, 6-1 defeat of Monica Seles. Hingis had to scramble initially as Seles, hitting the ball with most of her old power, got away to an explosive start but, as usual, Martina remained cool in the face of the onslaught and her defence held up. Soon Seles was making too many mistakes and Hingis took control of the match.
Looking forward to her match against Pierce who is her doubles partner, Hingis said, "She's been playing awesome. We played each other in the semis last week in Scottsdale. It wasn't a great match but it was one of those semi finals you have to play. It's nicer if you have a doubles partner you're not going to meet in the first or second round. The relationship is much better when you've both made it as far as the semis."
The other semifinal has second seed Lindsay Davenport playing Elena Dementieva. They secured their spots the day before.