Last year at the Key Biscayne tournament in Florida, Richard Williams claimed he was going to buy the Rockerfeller Centre for just over two billion dollars. It was his way of expressing his faith in Venus and Serena's ability to bring home prize money. His daughters' talent has never been an issue. The son of an impoverished cotton sharecropper, Richard has always been dreaming. Why stop now?

Casting his eye over their practice session yesterday morning, Williams was again preparing the girls for a match - a doubles against Martina Navratilova and Mariaan de Swardt.

If anything, the players represented Richard's new tennis model against an older outdated concept. Even Navratilova, who was responsible for taking women's tennis to a higher level in terms of fitness and athleticism, never possessed the powerhouse physique of either of the sisters.

In the beating of Martina Hingis by Venus, the demolition of Lisa Raymond by Serena and also Lindsay Davenport's third set crushing of Monica Seles, the bigger game has taken another leap forward. Unthinkable a year ago, but even the canny Hingis is finding the pace too hot.

The doubles match was interesting in itself, but for those looking for stark imagery, the contest was too good to be true.

Serena volleyed a ball into Navratilova's shoulder in the eighth game before Venus hit her on the head in the third set, providing a fitting metaphor for the brash arrival of the new and the current position of tennis of another era, the pre-Williams era.

The Williams sisters' victory brought Richard's pipe dream of the Rockerfeller Centre some £338,620 sterling closer, but today's contest could well be a more defining moment for the siblings' relationship.

So far, they have played each other on four occasions. The older sister, Venus (20), won the first three matches while Serena (18), showing a marked improvement in her game, won the last meeting in the final of the 1999 Compaq Grand Slam Cup.

No doubt Serena has been more impressive in her Wimbledon run, dropping only 11 games in five matches, while Venus lost 23. At yesterday's interview Venus was certainly in charge, laying down the ground rules. Whether she can take that onto court today is open to question.

Davenport's confidence coming into the tournament was still in the Roland Garros recovery room when she suddenly started playing well against Monica Seles. In Grand Slams that is the sought-after sign for a player who has serious intentions of going a long way.

Facing Jelena Dokic, Davenport faces a player on form rather than an adversary who has shown anywhere else that she can win this match. In those terms, the match belongs to Davenport if she plays to the level that won her last year's crown.

The injured back and the leg strapping have suggested that her mobility is suspect but that has already been put to bed. What should be an obstacle is Dokic's youthful fearlessness in what has been her best ever run in a Grand Slam event.

"I think my game is suited to this surface," said Dokic. "It's a fast surface, the one that suits the attacking players, the aggressive players. That's my type of game, that's probably why I do really well here."

Not there yet but Dokic, even if she does not have the physique to play a game similar to the three other semi-finalists, is thinking like them.