How Did Errani Win? Smart Adjustments Sara Errani continued her string of upsets at the French Open as she toppled Samantha Stosur in a match that featured huge momentum swings, shrewd tactical adjustments, and a tricky, swirling wind on Court Phillippe Chatrier. While Stosur's game plan was to use her big kick serve and top-spin forehand to dominate her service games, Errani had to make two key adjustments to negate Stosur's big game. One way to think about tennis is to divide the game into two parts, the service game, and the return game. Stosur has the best top-spin kick serve in the women's game, and she can use it as an offensive weapon on both the first and the second serve. In the ad court especially, Stosur positions herself about eight feet away from the center line. This creates a great deal of angle out wide, and the kick serve takes opponents off the court to return. Because the ball is kicking up and away from the receiver, Stosur frequently gets to start the rally with her favorite shot - the forehand - and an open court. Against Dominika Cibulkova in the quarterfinals, Stosur took advantage of Cibulkova's decision to stand well behind the baseline to return, and kicked her wide in the ad whenever she needed a point. Although Cibulkova had 10 break points on Stosur, she converted just once, as Stosur's serve to the ad court gave the powerful Australian a huge advantage. The kick serve is less of a weapon in the deuce court because of the different angle; the ball breaks toward the center of the court rather than out beyond the sideline. Errani stood in tight on the baseline to take Stosur's serve on the rise. It was an important adjustment, mainly because it allowed Errani to at times take away Stosur's favorite pattern. Not all the time, but often enough to break Stosur four times. At the beginning of the match, Errani was broken in her first service game as Stosur ripped forehand winners off of Errani's weak second serve. After breaking Stosur right back (a big early shift in momentum) Errani began to hit high-percentage spin serves as her first serve. Her service motion is awkward, as Errani opens her racket face to the sky on the takeback, and she fails to generate much racket head speed on impact. But she covered up that weakness by making 86 percent of her first serves. Errani excelled in two other areas of the match: managing the ever-shifting pressure in the match, and also handling the gusty, cool conditions. Errani played the match knowing she could win, but firmly in the role of the underdog. Stosur had never lost to Errani before Thursday, and had much more experience on the big stage of a Grand Slam semifinal. Stosur played her best tennis Thursday when she got behind. After losing the first set, she played a confident, aggressive second set. But Stosur faltered badly in the beginning of the third set, falling behind 3-love before recovering to tie the score at 3-all. Here, Errani steadied herself and held serve, hitting a deft forehand drop shot that died in the wind, and also using her forehand to run Stosur and keep control of the point. Like David Ferrer, who succeeds on the men's tour despite his small stature, Errani is a deceptively aggressive player. She is fearless at stepping up into the court and ripping the cover off anything short. She excels at running her opponent from side to side then attacking with an inside-in forehand. Her footwork, honed from years of soccer and basketball as well as tennis, allows Errani to get into superb position for each shot. In Thursday's windy conditions, Errani's ability to adjust to the ball in the wind was superior to Stosur's. On Saturday Errani will face Maria Sharapova in the women's final. Sharapova will be an overwhelming favorite, as she continues her remarkable clay court season. Under the tutelage of Thomas Hogstedt, Sharapova has improved her movement on clay, as well as her ability to play longer points. Like Stosur, Sharapova will look to feast on the Errani serve, and it will be fascinating to see if Errani can come up with an answer to Sharapova's power.