It's hard to overlook a former world No. 1 player and 2003 U.S. Open champion -- particularly on the grounds of the USTA's National Tennis Center. But when she is the soft-spoken Justine Henin-Hardenne, at 5 feet 5 1/2 and 126 pounds, a slip of a girl among the towering women who dominate the game, the oversight is easier to understand.

The U.S. Open is just the eighth tournament Henin-Hardenne has entered this year, while some of her peers are playing in their 28th. But with her third-round victory over 75th-ranked Cho Yoon Jeong on Saturday, she took her next quiet step into the second week of the season's final Grand Slam event, defeating the South Korean, 6-0, 7-6 (7-4).

It has been a season of extremes for Henin-Hardenne. It opened with disappointment, as she was forced to skip the Australian Open after suffering a right knee fracture in December. She returned months later in sterling form, winning her second French Open only to be bounced in the first round of Wimbledon weeks later by Eleni Daniilidou of Greece.

The devastating loss underscored the lesson her doctors and her own common sense had been telling her for months, ever since she contracted a mysterious viral illness that sidelined her for much of 2004. That is: There's no substitute for adequate rest. And even though she's just 23, her body demands careful tending if she wants to continue competing for several more years.

So Henin-Hardenne has made a science out of parceling out her energy, as if she has a finite number of quality matches left. When she does take the court, she doesn't mess around with mediocrity, boasting a 34-3 record this season that represents the highest winning percentage (.919) on the women's tour.

Henin-Hardenne has yet to drop a set in three rounds at the U.S. Open. Until Saturday, she hadn't allowed an opponent to win more than four games in a set.

As for the lack of attention she receives compared with that lavished on the sport's reigning divas -- top-seeded Maria Sharapova and the bejeweled Williams sisters, who share four U.S. Open titles between them -- Henin-Hardenne hardly minds.

"I'm going to try to prove on the court that I'm part of the players who can go to the end of the tournament," she said Saturday. "I don't care about that."

Williams Sisters Face Off

Venus and Serena Williams typically dread facing each other in Grand Slam events. But they found a bit of humor in it after their victories on Friday ensured they'll meet in a fourth-round match on Sunday.

Asked how she usually prepares to play her big sister, Serena smiled and said, "When I was winning all the Grand Slams, I poisoned her food."

Countered Venus, "She doesn't know that I have a food taster."