When Mary Pierce reigned among the world's top tennis players a decade ago, her anguish was palpable. No matter what she achieved -- whether winning the 1995 Australian Open or her beloved French Open in 2000 -- it was never enough to drain the tension from her body or lift the scowls from her face.

Today, as a 30-year-old woman, Pierce has made peace with the domineering father whose demands she could never satisfy and, as a result, put tennis in its proper perspective. No longer driven by the mad chase for high rankings and lucrative endorsement deals, Pierce is still competing because the game remains the best measuring stick of her ability -- regardless of how the sport's computers rank her or how manufacturers asses her worth as a corporate pitchwoman.

And she's playing the best tennis of her career.

She reached the final of the French Open in June and will take the court at Arthur Ashe Stadium on Friday vying for a place in the final of the U.S. Open. She'll face last year's runner-up, sixth-seed Elena Dementieva, in the first of two women's semifinals.

They will be followed by top-seeded Maria Sharapova and fourth-seeded Kim Clijsters, who'll battle for the other spot in Saturday's final.

All but Pierce were part of the pre-tournament prognostications. Even the sagest tennis insider didn't give Pierce a mention or a shot. But there has been nothing flukey about Pierce's march to her first U.S. Open semifinal. She is the only women's semifinalist who has yet to drop a set, sailing past three seeded opponents -- Jelena Jankovic (17th), Justine Henin-Hardenne (seventh) and Amelie Mauresmo (third) -- without displaying even a semblance of fatigue.

"It seems like she's really enjoying herself," says two-time U.S. Open champion Tracy Austin, an analyst for USA Network. "She's able to smile out there. She's really fit. And she has that big, first-strike ability to get ahead early."

Starting fast will be key against Dementieva, whose power and tenacity compensate for a weak serve. Dementieva's grit and resolve were enough to upset a listless Lindsay Davenport in the quarterfinals.

Just 22, Clijsters has advanced to the finals of four Grand Slam events and faltered each time (falling on three of those occasions to Henin-Hardenne). But if she can weather Sharapova's booming serve and punishing groundstrokes, Clijsters may well get that elusive title here in New York.