The official rule book of tennis is 35 pages long. For the most part, the document is a case study in compulsive precision. Here are a few of the exacting guidelines:
- If a tournament is played above 4,000 feet, pressureless tennis balls must be “acclimatized” for at least 60 days at the local altitude.
- The cord holding up the net cannot be thicker than ⅓-inch in diameter, and must be covered by a white band between 2 and 2.5 inches wide.
- The frame of the racket cannot exceed 29 inches in total length.
- The organizers of tennis tournaments must announce in advance their ball-change policy.
Amid all this punctiliousness, however, the rulebook contains one glaring omission: There are no rules about the surface of the court. While the boundaries of the space are carefully specified — it must be a rectangle, 78 feet by 27 feet, with a one-inch-wide center service line — there are zero references to the different materials on which the game can be played. It’s as if clay, grass, and hard court don’t exist, as if the composition of the playing field doesn’t matter.
This oversight has profoundly shaped the development of the sport. Because there are no rules about court surfaces, modern tennis is played on a stunning variety of materials, from the crushed brick of Roland Garros to the manicured lawns of Wimbledon. In fact, the International Tennis Federation (ITF), the regulatory body overseeing the sport, currently recognizes more than 160 different kinds of tennis courts, including surfaces made of carpet, clay, gravel, concrete, wood, asphalt, and fake grass.