PARIS -- Walking purposefully to her place at the baseline to receive serve, Justine Henin caught the eye of her coach of 14 years, Carlos Rodriguez.
She led Samantha Stosur 4-3 in the final set, but the resolve she wore on her face -- and a quietly clenched fist -- sent this message: I've got this.
But Stosur, the powerful player from Brisbane, Australia, held serve, and ultimately, it was Henin, the seven-time Grand Slam singles champion, who was a victim of badly frayed nerves Monday on Court Suzanne Lenglen. She played miserably the last two games, her beautiful backhand abandoning her completely, and Stosur prevailed 2-6, 6-1, 6-4.
Many had envisioned a fifth French Open title in six attempts for Henin, who missed the past two events at Roland Garros because of retirement. She reached the Australian Open final in only the second tournament of her comeback, losing to Serena Williams.
But instead, it will be Stosur -- the best player on clay this spring (now a sparkling 18-2) among women -- who advanced to meet Williams in a Wednesday quarterfinal match.
Earlier, Williams thumped Shahar Peer 6-2, 6-2, looking very much like a No. 1 seed. With Henin gone, her chances of scoring a second career French Open title seem more likely.
Afterward, Serena was asked whether she had been anticipating a match with Henin.
"No," Serena said. "You can never underestimate anyone, and Sam is actually a wonderful clay-court player. I think she proved that last year, and this year I think she's only lost twice on the clay.
"She's amazing. She's fast, strong, and has a great serve. I don't know if she has a real weakness. She plays a real all-around game, so I think that's what makes her like a real modern, really good player."
Henin, who spent five days in a row on the court with two matches that were suspended, looked tired in the third set. She said her third-round match with Maria Sharapova took a lot out of her emotionally.
"I knew 2010 would be difficult," said Henin, who described her prematch mindset as nervous and upset. "I took this year as a year of transition. All the expectations are coming from the outside. Everyone saw me at the level I was.
"It took me many years to get at that level. I was really here to play match to match. I didn't consider myself as the favorite."
While there was so much attention focused on Henin's match with Sharapova and even more anticipation of a possible quarterfinal opposite Serena, Stosur lurked in between, overlooked and vastly underappreciated.
Stosur has won 24 of her past 28 matches overall. She had never played Henin until a month ago, when she lost a three-set match in Stuttgart. She won five straight games to take a lead in that frame, but Henin won the match with six straight games of her own.
"Justine was just too good," Stosur observed. "She broke me three times in a row."
Which is why Henin looked so confident in the late stages of Monday's match. History seemed destined to repeat itself, but Henin couldn't conjure her championship form.
She double-faulted off the tape, then sent a backhand wide to lose her serve at 4-all. And then there were three backhands into the net, wedged around an exquisite drop shot. After Stosur double-faulted on her first match point, she raced to the net and pounded an overhead for the victory.
Henin's weak second serve probably cost her the match; Stosur won 22 of 36 points when Henin was in that vulnerable position. Stosur's best advancement in a major came here a year ago, when she reached the semifinals, losing to eventual champion Svetlana Kuznetsova.
No Australian woman has won a Grand Slam singles title since 1973. Stosur, who has matured relatively late, at the age of 26, is only three matches away.
"She improved a lot the last few months," Henin said. "We can see she is in confidence also. She's calm on the court, very quiet. Very, very good player."
Said Serena: "So she's someone you can't overlook. She has a good chance to go all the way."
Greg Garber is a senior writer for ESPN.com.