Most of the bounce in a tennis ball comes from its internal air pressure. The hotter the weather, the greater that air pressure, and the higher the ball will bounce. One of the many advantages of hitting heavy topspin is making the ball kick to a height where your opponent cannot strike the ball as comfortably. Nadal hits very heavy topspin on both his forehand and his backhand, and in today's 90-degree heat at Roland Garros, Federer was hitting the majority of his shots at an uncomfortable height. High balls are especially tough for a one-handed backhander like Federer. The heat also made it more difficult for Federer to send Nadal sliced balls that would stay low. With Nadal's Western forehand grip, high balls are much easier to handle than low ones in general, and Nadal would have had much more difficulty hitting high-kicking topspins to Federer on balls that were too low to allow much of an upward brush by his racquet.
More topspin would have helped Svetlana Kuznetsova against Justine Henin-Hardenne. Svetlana can generate topspin quite well, and she could have used it more often to kick the ball high to Justine's one-handed backhand, much as Amelie Mauresmo did so effectively at the Australian Open in January. Henin-Hardenne won 6-4, 6-4 with great court coverage; a mixture of angles, depth, and power on her groundstrokes; and solid serving. Svetlana's biggest shot is her forehand, but she went for too much too often instead of using the safer topspin to extend points, keep the ball above Justine's strike zone, and make Justine work harder for each point. Justine was starting to look fatigued in the second set, so longer points would have worked to Svetlana's advantage in both the short and the long term. With this third French Open title, Justine has, like Rafael, established herself as the toughest current player on clay.
