Oudin Twins Have No Plans to Replace Venus and Serena

They all know who Melanie is," said Katherine of her classmates. "Her tennis has been skyrocketing. In the past year or so, I haven't seen much of her. It's so sad to say."

But Katherine hears about Melanie all the time. In July, while hitting tennis balls at the neighborhood courts with a friend, Katherine overheard two other players talking about how impressed they were with her sister's All-England Club star turn.

The fact that Melanie has been able to back it up with a strong showing at the U.S. Open, where she'll try to knock of another tall, blond, highly-ranked Russian, has all of the Oudins excited.

"To me this win put into concrete her credibility," said the twins' mother, Leslie Oudin, after Melanie's second-round victory over Dementieva. "That's something I'm really happy about; that it wasn't just a fluke and she can be a top-notch player."

Melanie and Katherine are, by their own admission and confirmed by mom, polar opposites.