Clay surface

A clay court is one of many different types of tennis court. Clay courts are made of crushed shale, stone, brick, or other unbound mineral aggregates. The French Open uses clay courts, making it unique among the Grand Slam tournaments. Clay courts are more common in Continental Europe and Latin America than in the United States, Canada or Britain. Two main types exist: red clay, the more common variety, and green clay, also known as "rubico", which is a harder surface. Although less expensive to construct than other types of tennis courts, the maintenance costs of clay are high as the surface must be rolled to preserve flatness. The water content must also be balanced; green courts are often sloped in order to allow water run-off.

Clay courts favor the "full western grip" for more topspin. "Clay-courters" generally play in a semicircle about 1.5 to 3 metres (5 to 10 feet) behind the baseline.

Clay courts are considered "slow", because the balls bounce relatively high and more slowly, making it more difficult for a player to deliver an unreturnable shot. Points are usually longer as there are fewer winners. Therefore, clay courts heavily favor baseliners who are consistent and have a strong defensive game, which has allowed players such as Rafael Nadal, Björn Borg, Chris Evert, and Justine Henin to find success at the French Open.

Clay court players use topspins to throw off their opponents. Movement on gravel courts is very different from movement on any other surface. Playing on clay often involves the ability to slide into the ball during the stroke, as opposed to running and stopping like on a hard or grass court. Players who excel on clay courts but struggle to replicate the same form on fast courts are known as clay-court specialists.

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