Apart from a short period in the second set, Cibulkova had been in over her head all afternoon -- often literally. Stosur's shots bounced up high, leaving Cibulkova flailing her racket like a helicopter wing.
Afterward, she looked for words to describe the experience.
"I have to say that she played unbelievable today," Cibulkova said. "Her topspin and her serve … I mean, she played like a man, and it's really hard to play against a man."
Cibulkova said she could do little except wait for the storm to let up, but the wait was in vain. "Yeah. I felt [like I was] playing against a man today," she said.
It's a phrase WTA players occasionally use for certain opponents, but what does it mean to "play like a man" in today's game? It clearly isn't about sheer pace. The description has been applied to players like Stosur, Justine Henin, Svetlana Kuznetsova and, once in a slightly more controversial context, Amelie Mauresmo.
So what do players like the petite Henin, the broad-shouldered Mauresmo and the strong-legged Kuznetsova have in common with Stosur? It goes back to the beginning of Cibulkova's description: the topspin and the serve. Stosur's kick serve and big topspin forehand are what set her apart from the rank-and-file of women's players.
It's not as much about power as it is range. The amount of spin Stosur generates makes her shots bounce higher and feel heavier. Rafael Nadal's cannonball forehand is the epitome of this phenomenon, but few men -- and by far, even fewer women -- can get close to getting that kind of action on the ball.
Slice has also been part of the equation, as it was for Henin and Mauresmo, with their one-handed backhands. In Stosur's case, she can also add variety to her game by coming into the net behind her huge topspin forehand. But despite her previous doubles prowess, she is often hesitant up there. Stosur's bigger weapon is her kick serve, particularly on clay, where it bounces up even higher and above her opponents' comfort zone.
Why do so few women play this way? For one thing, it requires a lot of strength. Stosur has that, as her muscular frame and bulging biceps show. But, she says, it involves practice and skill as well as the requisite physical base.
"It's probably a bit of both," Stosur said. "I think even the girls that you look at on tour that you don't necessarily think they're very big or very strong, they can hit the ball very hard. That's all through technique and timing of the ball."
For Stosur, it has become second nature.
"I find it a lot easier to play that way than the way that most of the girls play," she said. "I think that a big part of the serving factor is when I was young, I had a coach that maybe saw the potential in me to be able to hit that kick serve. From 10, 11, 12 years old, I worked on it, worked on it and worked on it. As you get older, and you get stronger and get bigger, it becomes more and more effective. So I think that probably was ingrained in me probably from a young age.
"And then the spin and all that, just kind of growing with my game and working with David [Taylor] has really improved that the last four or five years that we've been together."
Though the reigning U.S. Open champion cites hard courts as her most comfortable surface, Stosur's game first began to impose itself on the clay courts of Paris, where she reached her first Grand Slam final in 2010. She will attempt to return to that stage again in Thursday's semifinals, when she will face Sara Errani, a speedy Italian who also likes to hit with spin and variety. But Errani, at 5-foot-4, does not stand much higher than Cibulkova, which partly helps explain why Stosur has won each of their five previous meetings and is the favorite again.
Either way, however, the action on the court should include a lot of action on the ball.
Sharapova versus Kvitova
How much has Maria Sharapova improved on clay? She fell flat on her back during her fourth-round match, but despite looking a bit shaken, she got right back up.
"That was my first fall of the clay season, which is the biggest shocker," she joked afterward.
It came earlier last year, when she fell forward on to the clay in the Rome semifinals.
"I thought I was on the cliffs of Italy and forgot there was no water out there," she said at the time.
She'll need to stay steady when she goes up against Petra Kvitova in the women's semifinals, their third meeting in the past four Grand Slams. Not counting a retirement loss to Kvitova in Tokyo last year, Sharapova has won three of their four meetings. But Kvitova's lone victory was the big one -- last year's Wimbledon final. Sharapova avenged that loss with a win over Kvitova in the Australian Open semifinals.
"The Wimbledon was something special for me," Kvitova said. "It was first final. I was No. 8 and she was the favorite in this match. I haven't something to lose so I just play my game. In the beginning of the year, Australia, I didn't practice too much."
They also met on indoor clay at Stuttgart earlier this season, with Sharapova prevailing in a tight encounter.
As it was at Wimbledon, this match in Paris could be difficult for Sharapova, if Kvitova plays at the top of her game. But the Czech's form tends to fluctuate, while Sharapova has stood out for her consistency over the past year. He has been the best performer on the red clay this season.
Sharapova also has more on the line: She could return to No. 1 by defeating Kvitova and reaching the final. And winning this event would be her first major victory following shoulder surgery, as well as the final piece of a career Slam.